Immune system modulators

ABSTRACT

The present invention described herein relates to the composition that interact with molecules that suppress the immune system. More specifically, embodiments described herein concern the discovery, manufacture, and use of compositions that remove immunosuppression the immune system by binding to immunoregulatory peptides that interact with receptors on immune cells, compositions the can stimulate immune cells, and compositions that are cytotoxic to tumor cells,

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/916,512 filed Mar. 3, 2016, now U.S. Pat. No. 9,657,059 B 2, which isa U.S. National Phase of PCT International App. No. PCT/US2014/054612,filed on Sep. 8, 2014, designating the United States of America andpublished in the English language, which claims the benefit of U.S.Provisional Application Ser. No. 61/875,598, filed Sep. 9, 2013, whichis hereby incorporated by reference in its entirety.

SEQUENCE IN ELECTRONIC FORMAT

The present application is being filed along with a Sequence Listing asan ASCII text file via EFS-Web. The Sequence Listing is provided as afile entitled CANIG005WO.TXT, created and last saved on Sep. 8, 2014,which is 162,189 bytes in size, and updated by a file entitledCANIG005C1SEQUENCE.TXT, created and last saved on Apr. 27, 2017, whichis 203,994 bytes in size. The information in the electronic format ofthe Sequence Listing is incorporated herein by reference in its entiretyin accordance with 35 U.S.C. § 1.52(e).

FIELD OF THE INVENTION

Aspects of the present invention generally relate to compositions thatinteract with molecules, which suppress the immune system. Morespecifically, embodiments described herein concern the discovery,manufacture, and use of compositions that modulate the immune system.

BACKGROUND OF THE INVENTION

The immune system is finely tuned to detect and eradicate foreignmolecules and, at the same time, avoid over reactivity, which couldresult in destruction of normal tissues resulting in autoimmune orchronic inflammatory diseases. The initiation of a specific immuneresponse is a well-orchestrated chain of events culminating in theactivation of effector functions, such as the release of cytokines,production of specific antibodies and/or cellular cytotoxic activity.

The role of the immune system in human cancer has been under debate forseveral years. It has been puzzling, for example, that an increasedincidence of malignant tumors is not observed in immunocompromisedanimals, such as nude mice. These animals are not as profoundlyimmunocompromised as one would expect, since they are able to mountsignificant anti-tumor immune reactivity. When severelyimmunocompromised transgenic mice of the Stat 1−/−, IFNγR −/−, orRAG2−/− genotypes were studied, the tumor incidence and theimmunogenicity of cancers growing in these animals strongly supportedthe existence of an immune mediated anti-cancer reactivity with thecapacity to control cancer development. Based on these results, theimmunoediting model was developed (Dunn and Schreiber, Immunity,21:137-148 (2004)).

Similarly, the modest increase in cancer incidence in therapeuticallyimmunosuppressed, allo-organ transplanted patients seems to be explainedby the early appearance of immunosuppression in epithelial cancers(Schüle J, et al., Breast Cancer Res Treat. 2002; 74:33-40; Wolfram R M,et al., Int J Cancer. 2000; 88:239-44, Petersen R P, et al., Cancer.2006; 107:2866-72). The occurrence of spontaneous immune-mediated tumorregression, the correlation between tumor-infiltrating lymphocytes andprognosis, the occurrence of tumor specific cytotoxic T-lymphocytes andantibodies and the efficacy of immunostimulatory treatment all support asignificant role of the immune system in the control or regulation ofcancer progression.

These observations are also consistent with the results of Clinchy etal. (Clinchy B, et al., Cancer. 2007; 109:1742-9), showing thatdysregulation of the immune system in cancer, with an enhanced capacityto produce IL-6, correlate to poor prognosis in radically resectedcolorectal cancer patients. Not even in the group of high risk patientswith locally advance tumors, T3N1-2, did patients die from their cancerif their immune cells exhibited a normal production of IL-6. Similarly,Galon et al. (Galon J, et al., Science. 2006; 313:1960-4, Mlecnik B, etal., J Clin Oncol. 2011, 29:610-8) have shown that T-cell immuneparameters strongly correlate to the prognosis in these patients.

The majority of human cancers of different origin induce immune mediatedanti-tumor reactivity, but immunosuppressor mechanisms often appearingat an early stage, compromise the immune system. The existence ofregional immunosuppression in the absence of systemic suppression(concomitant immunity), indicates a regional, systemic gradient ofimmunosuppression (Gorelik E., et al., Adv Cancer Res. 1983; 39:71-120).For instance, the function of immune cells can be more impaired near thetumor than in peripheral blood (Vose B M, et al., Int J Cancer 197720:895-902). Several factors may mediate this suppression(Ménétrier-Caux C, et al., Br J Cancer 1999 79: 119-130, Heimdal J H, etal., Scand J Immunol 2000 51: 271-278, Heimdal J H, et al., Scand JImmunol 2001 53: 162-170), but no fundamental mechanism has beenidentified (Kim R, et al., Cancer Res. 2006 Jun. 1; 66(11):5527-36,Mocellin S, et al., J Immunother 2001 24:392-407). The impact of thehostile intra-tumoral milieu has been described by several groups(Perdrizet G A, et al., J Exp Med. 1990; 171:1205-20, Yu P, et al., JExp Med. 2005 201:779-91.) Immune reactivity against cancer can besuppressed at various levels, e.g., initiation, recruitment of effectorcells to the tumor and migration of these cells within the tumor andtheir cytotoxic activity. Effector mechanisms present at the tumor sitecan also provide immune mediated cancer control.

Although data indicate that the immune system is of major importance forcancer control (Dunn G P, et al., Immunity. 2004 21:137-48, Galon J, etal., Science. 2006 313:1960-4, Koebel C M, et al., Nature. 2007450:903-7, Clinchy B, et al., Cancer. 2007 109:1742-9, Teng M W, et al.,J Leukoc Biol. 2008 84:988-93) malignant tumors continue to grow and theefficacy of immunotherapy is rather poor with an objective remissionrate of 10-20%. There can be several reasons for this apparent paradox,e.g., tumors avoid recognition by the immune system due to tumorantigens being weak self-antigens, poor antigen presentation due todown-regulation of TAP and MHC I and II) or induction of tolerance orcancer related immunosuppression. The impact of an hostile intra-tumoralmilieu is demonstrated by results from animal experiments (Perdrizet GA, et al., J Exp Med. 1990; 171:1205-20, Yu P, et al., J Exp Med. 2005201:779-91) and human tumors (Gajewski T F, et al., J Immunother. 200629:233-40, Whiteside T L, Oncogene. 2008 27:5904-12).

Different types of immunosuppressor cells, regulatory T-cells, immaturedendritic cells (iDC), tumor associated macrophages (TAM) and myeloidderived suppressor cells (MDSC), can function substantially in cancerrelated immunosuppression. The immune balance is generally skewed to aTh2 dominance characterized by cytokines, such as IL-4, IL-10 and PGE2.Additionally, other immunosuppressor mechanisms, such as serum blockingfactors, circulating immune complexes, enhanced IL-1Ra production andenhanced intra-tumoral proteolytic activity can function in cancerrelated immunosuppression.

While investigating mechanisms for induction of interleukin-6 (IL-6) incancer patients, immunoregulatory peptide sequences derived from serumalbumin were found (see e.g., U.S. Pat. Nos. 7,960,126; 8,110,347; and8,110,347; as well as, US Publication No. 2010/0323370, each of which ishereby expressly incorporated by reference in their entireties.Interleukin-2 (IL-2) plays a major role in initiation and activation ofthe immune response and its capacity to induce lymphokine activatedkiller cells (LAK-cells), T-cell proliferation and cytotoxicity. Severalreports have shown that peripheral blood mononuclear cells (PBMC) fromcancer patients have a diminished capacity to both synthesize (Wanebo HJ, et al., Cancer. 1986 57:656-62, Mantovani, G., et al., Diagn. Clin.Immunol. 1987 5: 104-111, Lauerova L, et al., Neoplasma 1999 46:141-149) and respond to IL-2 (Tsubono M, et al., J Clin Lab Immunol 199033:107-115, Pellegrini P, et al., Cancer Immunol Immunother 199642:1-8). Soluble products from tumor explants or serum from cancerpatients can inhibit cytokine production, inhibit IL-2 receptorexpression (Botti C, et al., Intl J Biol Markers 1998 13:51-69, LauerovaL, et al., Neoplasma 1999 46:141-149) and/or reduce the proliferativecapacity in normal T lymphocytes (Botti C, et al., Intl J Biol Markers1998 13:51-69).

Integrins are a superfamily of transmembrane glycoproteins, foundpredominantly on leukocytes that mediate cell-cell and cell substratuminteractions. Integrins play an important role in immune regulation, aswell, in particular αLβ2, (Leukocyte Function Associated molecule-1,LFA-1) is of pivotal importance for the initiation and regulation of animmune response, tissue recruitment and migration of inflammatory cellsand cytotoxic activity of lymphocytes (Hogg N, et al., J Cell Sci. 2003116:4695-705, Giblin P A, et al., Curr Pharm Des. 2006 12:2771-95, EvansR, et al., Cell Sci. 2009 122:215-25). In addition, LFA-1 is involved inthe proliferative response to interleukin-2 (Vyth-Dreese F A, Eur JImmunol. 1993 12:3292-9) and some fragments of albumin bind to LFA-1and/or the IL-2 receptor thereby modulating the functional propertiesmediated through these receptors including immune cell proliferation(see U.S. Publication No. 2011/0262470, which is hereby expresslyincorporated by reference in its entirety). Despite these advancements,the need for more compositions to modulate the immune system, especiallyin individuals that have a compromised immune system and/or cancer, ismanifest.

BRIEF SUMMARY OF THE INVENTION

Several molecules that regulate the immune system have been discovered.As described herein, many peptides (e.g., peptides obtained fromenzymatically cleaved or denatured albumin and/or albumin fragments)bind to receptors (e.g., IL-2 and/or LFA-1 receptors) on human immunecells and thereby inhibit several immune cell functions or properties(e.g., lymphocyte proliferation, leukocyte spreading/migration, naturalkiller cell (NK-cell) cytotoxicity), which are central to maintaining ahealthy immune system. Interestingly, a significantly enhanceddegradation of albumin was found to occur when resistance to treatmentdeveloped in a mouse model (Culp W D, et al., J ProteomeRes. 2006;5:1332-43). Accordingly, some embodiments include molecules that are orthat structurally resemble or mimic albumin-derived immunoregulatorypeptides or structures (e.g., synthetically derived mimics or analogs,or peptidomimetics), which bind to and/or interact with receptors onhuman immune cells and inhibit or suppress the immune system (e.g.,reducing lymphocyte proliferation, leukocyte spreading/migration, and/orNK-cell cytotoxicity). Additionally, several molecules were developedthat bind to and/or interact with albumin-derived immunoregulatorypeptides or structures to inhibit the interaction of the albumin-derivedimmunoregulatory peptides or structures with receptors on human immunecells. For example, antibodies and peptides that bind to thealbumin-derived immunoregulatory peptides or structures were made andthese inhibitors of albumin-derived immunoregulatory peptides orstructures were found to interfere with the ability of thealbumin-derived immunoregulatory peptides or structures to inhibit orsuppress immune cell function.

Preferred inhibitors of albumin-derived immunoregulatory peptides orstructures, such as P28R (SEQ ID NO: 2) or P28 core (SEQ ID NO: 62),were identified using the methods and approaches described herein. TheP28R and P28 core inhibitors, for instance, was found to de-block (e.g.,displace bound immunoregulatory peptides or 3028 structures from animmune cell receptor, such as LFA-1), remove or displace thealbumin-derived immunoregulatory peptides or structures that were boundto or associated with immune cell receptors (e.g., LFA-1) and therebyrestore normal immune cell function (e.g., immune cell proliferation inresponse to an inducer, such as IL-2, activation or stimulation of animmune cell, as evidenced by an increase in CD69 or CD71 expression,induction of the secretion of a signal substance, as evidenced byinterferon gamma or IL-12 production, or stimulation of the release of acytolytic substance, as evidenced by the release of granzyme B orperforin, enhanced cytotoxicity, cytokine production, cell migration,and/or cell proliferation). As such, it is contemplated herein that inaccordance with some embodiments herein, P28R and P28 core can induceenhanced cytotoxicity, cytokine production, cell migration, and/or cellproliferation. P28R was also found to directly stimulate immune cellsand induce cytotoxicity in tumor cells. It is contemplated that severalother inhibitors of albumin-derived immunoregulatory peptides orstructures can be developed using the teachings described herein.Accordingly, aspects of the invention include peptides, modifiedpeptides, peptidomimetics, aptamers, antibodies, and fragments thereof,which bind to immunoregulatory structures, such as albumin-derivedimmunoregulatory peptides or structures, as well as, methods ofmanufacture, and methods of use thereof, in particular, methods toreduce immunosuppression in a subject in need thereof (e.g., immunesuppression resulting from cancer or pathogenic, viral or bacterial,enduring or chronic infections, for example due to antibioticresistance).

Some embodiments of the invention relates to a compositions thatcomprise an isolated peptide comprising Formula VII, wherein Formula VIIis:

(SEQ ID NO: 394) X₇₀₀KX₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆KX₇₀₇X₇₀₈X₇₀₉X₇₁₀X₇₁₁EX₇₁₂

-   -   wherein X700 is K, A, D, E, G, H, I, L, M, N, P, Q, R, T, V, or        K, or absent;    -   wherein X701 is L, A, C, D, E, F, G, H, I, K, M, N, Q, R, S, T,        or V, or absent;    -   wherein X702 is D, A, E, I, V, W, or Y, or absent;    -   wherein X703 is T, C, M, N, P, Q, R, S, W, or Y, or absent;    -   wherein X704 is F, A, I, M, N, P, T, or V, or absent;    -   wherein X705 is F, L, M, Q, S, T or V, or absent;    -   wherein X706 is V, F, G, L, P, or R, or absent;    -   wherein X707 is L, A, F, G, I, M, N, P, Q, R, S, T, V, or Y, or        absent;    -   wherein X708 is S, H, M, N, Q, or T, or absent;    -   wherein X709 is L, A, H, I, M, N, Q, R, S, T, V, or W, or        absent;    -   wherein X710 is F, A, C, G, H, I, L, M, NP, Q, R, S, T, V, or W,        or absent;    -   wherein X711 is T, F, G, H, I, L, M, N, P, S, V, or W, or        absent; and    -   wherein X712 is R, F, K, N, R, T, or Y, or absent.

Said formula VII may be one of SEQ ID NO: 1-101, 167-172, 174-177,179-393, 396-581, or 582.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising Formula VIII, wherein Formula VIII is:

-   -   X₈₀₀K X₈₀₁K X₈₀₂E X₈₀₃ (SEQ ID NO: 395)    -   wherein X₈₀₀ is K, A, D, E, G, H, I, L, M, N, P, Q, R, T, V, or        K, or absent;    -   wherein X₈₀₁ is LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO:        597), EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV        (SEQ ID NO: 600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO:        602), LDTFSV (SEQ ID NO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV        (SEQ ID NO: 605), LDTFLV (SEQ ID NO: 606), LDGFFV (SEQ ID NO:        607), LDTFGV (SEQ ID NO: 608), LDTFFK (SEQ ID NO: 609), ADTFFV        (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611), DDTFFV (SEQ ID NO:        612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO: 614), IDTFFV        (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ ID NO:        617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV        (SEQ ID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO:        622), VDTFFV (SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV        (SEQ ID NO: 625), LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO:        627), LWTFFV (SEQ ID NO: 628), LYTFFV (SEQ ID NO: 629), LDCFFV        (SEQ ID NO: 630), LDMFFV (SEQ ID NO: 631), LDNFFV (SEQ ID NO:        632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQ ID NO: 634), LDSFFV        (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV (SEQ ID NO:        637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639), LDTNFV        (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:        642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG        (SEQ ID NO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO:        647), LDTFFR (SEQ ID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV        (SEQ ID NO: 650), LDTFAV (SEQ ID NO: 651), LDTFCV (SEQ ID NO:        652), LDTQFV (SEQ ID NO: 653), LDTLFV (SEQ ID NO: 654), LTTFFV        (SEQ ID NO: 655), LDTFFI (SEQ ID NO: 656), LDHFFV (SEQ ID NO:        657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ ID NO: 659), LDTFWV        (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQ ID NO:        662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV        (SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO:        667), LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV        (SEQ ID NO: 670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO:        672), LQTFFV (SEQ ID NO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV        (SEQ ID NO: 675), YDTFFV (SEQ ID NO: 676), LDEFFV (SEQ ID NO:        677), WDTFFV (SEQ ID NO: 678), LDTKFV (SEQ ID NO: 679), LDTCFV        (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681), LDTHFV (SEQ ID NO:        682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO: 684), LDLFFV        (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ ID NO:        687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT        (SEQ ID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO:        692), LDIFFV (SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV        (SEQ ID NO: 695), LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO:        697), LDTFFC (SEQ ID NO: 698), LDKFFV (SEQ ID NO: 699), LDTFKV        (SEQ ID NO: 700), LDTEFV (SEQ ID NO: 701), LDTFFW (SEQ ID NO:        702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQ ID NO: 704), LDTFFH        (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN (SEQ ID NO:        707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709), LDTFFD        (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO:        712), TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV,        LDV, LV, or L, or absent;    -   wherein X₈₀₂ is LSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716),        LQLFT (SEQ ID NO: 717), LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID        NO: 719), LHLFT (SEQ ID NO: 720), LSQFT (SEQ ID NO: 721), LSVFT        (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723), LSLMT (SEQ ID NO:        724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726), LSLNT (SEQ        ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),        LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID        NO: 732), LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR        (SEQ ID NO: 735), LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO:        737), FSLFT (SEQ ID NO: 738), GSLFT (SEQ ID NO: 739), ISLFT (SEQ        ID NO: 740), MSLFT (SEQ ID NO: 741), NSLFT (SEQ ID NO: 742),        PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744), RSLFT (SEQ ID        NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747), YSLFT        (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO:        750), LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ        ID NO: 753), LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755),        LSTFT (SEQ ID NO: 756), LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID        NO: 758), LSLIT (SEQ ID NO: 759), LSLLT (SEQ ID NO: 760), LSLTT        (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762), LSLWT (SEQ ID NO:        763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765), LSLFH (SEQ        ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),        LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID        NO: 771), LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT        (SEQ ID NO: 774), LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO:        776), LSKFT (SEQ ID NO: 777), LSCFT (SEQ ID NO: 778), LCLFT (SEQ        ID NO: 779), LRLFT (SEQ ID NO: 780), LPLFT (SEQ ID NO: 781),        LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783), LDLFT (SEQ ID        NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786), WSLFT        (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO:        789), LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ        ID NO: 792), LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794),        CSLFT (SEQ ID NO: 795), LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID        NO: 797), LSLFC (SEQ ID NO: 798), LFLFT (SEQ ID NO: 799), LELFT        (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801), LLLFT (SEQ ID NO:        802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804), LSLFE (SEQ        ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),        LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID        NO: 810), SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT,        LSL, LT, or T, or absent; and    -   wherein X₈₀₃ is R, F, K, N, R, T, or Y, or absent.

Said formula VIII may be one of SEQ ID NOs: 1-34, 64-68, 70-72, 74-77,80, 83, 86, 89, 92-96, 99-100, 264, 268-269, 270-386, 388-393, 396-401,403, 404, 406, 408-411, 413-416, 419-420, 422-438, 442-444, 446-449,451-453, 455-458, 460, 462-466, 470, 472-477, 479-480, 482-484, 486,487, 489, 491-493, 495-498, 500-508, 512-517, 519-522, 528-530, 532,533, 535-538, 540, 542-551, 553, 557-559, 567, 570, 572-581, or 582.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising Formula I, wherein Formula I is:

(SEQ ID NO: 166) XX₁VKX₂X₃X₄

-   -   wherein X is KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO: 168),        KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID        NO: 171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ        (SEQ ID NO: 254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO:        256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO: 258), KLDT (SEQ        ID NO: 172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO: 260), KLDQ        (SEQ ID NO: 261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO: 263),        LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, Q, or absent.    -   wherein X₁ is FF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT, AL,        VF, VM, VS, VV, VT, or VL, or absent;    -   wherein X₂ is LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH, or        absent;    -   wherein X₃ is LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT,        QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT,        VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT,        MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN,        LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN,        VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,        MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP,        LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP,        VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP,        MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR,        LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR,        QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR,        VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR; and    -   wherein X₄ is ER, E, or absent.

Said formula I may be one of SEQ ID NOs: 2-40, 46-52, 58-65, 67-71,74-77, 80-83, 86-88, 92-96, 99-101, 166, 173, 178, 182, 268-325,332-392-393, 396-415, 417-444, 446-468, 470-487, 489-494, 497-508, 510,512, 514-517, 520-522, 524-525, 528-533, 535-536, 538-539, 542-544, 546,548, 551, 553, 556-559, 561, 563-568, 571-573, 575-581 or 582, such assaid formula I may be one of SEQ ID NOs: 2 to 33.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising formula II, wherein formula II isXTFFVKLSX₁X₂(SEQ ID NO: 173),

-   -   wherein X is KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO: 175), KKGD        (SEQ ID NO: 176), KKED (SEQ ID NO: 177), KLD, LD, D, or absent    -   wherein X₁ is LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT,        QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT,        VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT,        MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN,        LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN,        VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,        MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP,        LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP,        VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP,        MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR,        LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR,        QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR,        VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR, or        absent; and    -   wherein X₂ is ER, or E, or absent, such as said formula II may        be one of SEQ ID NO: 2-5, 19-38, 46-49, 58-61, 64, 68-70, 75,        81, 87, 93, 94, 100, 101, 173, 268-303, 350-393, 396, 398, 399,        400, 402, 403, 405, 406-408, 412-414, 417, 418, 421-423,        426-428, 430, 431, 435, 436, 438, 439, 440-442, 448-455, 458,        459, 461, 465, 467, 468, 471, 475, 476, 478-481, 483, 485, 487,        489-491, 493, 494, 497-499, 503, 507, 510, 512, 514-517, 520,        521, 524, 525, 528, 529, 531, 533, 538, 539, 542-, 544, 546,        551, 556-559, 561, 563-568, 571-573, 575-577, 579, 580, or 581.        Other examples includes an isolated peptide, wherein X is KKLD        (SEQ ID NO: 174) or wherein X₂ is ER or wherein said formula is        TFFVKLSLFTER (SEQ ID NO: 49) or TFFVKLSLFTE (SEQ ID NO: 250) or        wherein said formula is KKLDTFFVKLSLFTER (SEQ ID NO: 2) or        KKLDTFFVKLSLFTE (SEQ ID NO: 34).

Some embodiments of the invention include compositions that comprise anisolated peptide comprising Formula III, wherein Formula III is:

(SEQ ID NO: 178) XX₁VKLX₂LX₃TEX₄

-   -   wherein X is KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO: 180),        LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent;    -   wherein X₁ is F, M, S, V, T, or L, or absent;    -   wherein X₂ is S, Q, M, T, or H, or absent;    -   wherein X₃ is F, M, Q, H, N, P, S, G, A, or R, or absent; and    -   wherein X₄ is R or absent.

Said formula III may be one of SEQ ID NO: 2-13, 15-18, 22-30, 34, 46-52,58, 64, 65, 70, 71, 76, 77, 82, 83, 88, 93-96, 99, 100, 178, 268-325.Examples includes wherein X is KKLDTF (SEQ ID NO: 178) or wherein X4 isR or wherein said formula is VKLSLFTER (SEQ ID NO: 52) or VKLSLFTE (SEQID NO: 251) or wherein said formula is KKLDTFFVKLSLFTER (SEQ ID NO: 2)or KKLDTFFVKLSLFTE (SEQ ID NO: 34).

Other examples includes isolated peptides comprising at least one of SEQID NOs: 1-101, 167-172, 174-177, 179-393, 396-581 and 582 or at leastone of SEQ ID NOs: 1-32, 34, 64-66, 68, 76, 94-96, 98, and 264-393 or atleast one of the sequences of Table 5.1.

The above mentioned isolated peptides, may have at least one amino acidbeing a D amino acid, artificial amino acid, or chemically modifiedamino acid and/or comprise an N-terminal acetyl group and/or comprise aC-terminal amide group and/or be glycosylated or nitrosylated.

The above mentioned isolated peptides may be joined to at least one ofpolyethylene glycol, a fatty acid, or a pharmacokinetic modifier and/orcomprises a cyclic peptide.

The above mentioned isolated peptides may comprise at least onemodification, for example at least one of a D amino acid and/or aN-terminal acetyl group and/or a C-terminal amide group and/orglycosylation and/or nitrosylation and/or carbonylation and/or oxidationand/or a linked pharmacokinetic modifier and/or a linked polyethyleneglycol or any combination thereof.

The above mentioned isolated peptides can be less than or equal to 1100amino acids in length, such as between 7 amino acids and 20 amino acidsin length.

The above mentioned isolated peptides may be joined to at least one of asupport, a carrier, and/or a fusion protein.

The above mentioned isolated peptides may be multimerized.

The above mentioned peptides may comprise a detectable label joinedthereto, such as a biotinylated label, a radioactive label, afluorescent label, or a colloidal gold label and/or comprise a cytotoxicagent joined thereto, such as a radiochemical, or a toxin.

The above defined peptides may be less than or equal to 50, 49, 48, 47,46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29,28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 16, 15, 14, 13, 12, 11, 10, 9,8, 7, 6 or 5 amino acids in length or any length in between any of thesenumbers.

Some embodiments of the invention relates to an isolated polynucleotidecomprising a sequence encoding any of the peptides disclosed above, suchas SEQ ID NOs: 2, 62, 102-165, 583-586, or 589. The invention alsorelates to a vector comprising the isolated polynucleotides. Thepeptides encoded by the isolated polynucleotide which may be present ina vector is less than or equal to 1100 amino acids in length, such asbetween 7 amino acids and 20 amino acids in length.

Some embodiments of the invention relates to a protein complexcomprising any of the isolated peptides mentioned above bound to atleast one of albumin, a fragment of albumin, a support, a carrier or afusion protein. The invention also relates to a method of making theprotein complex comprising:

-   -   contacting any of the above defined peptides with a biological        sample obtained from a human subject, wherein said biological        sample comprises albumin or a fragment thereof; and    -   detecting the presence of said protein complex.

Said peptides may for examples be attached to a support.

Some embodiments of the invention relates to a method of detecting thepresence of an albumin or an albumin fragment in a biological samplecomprising:

-   -   contacting any of the above defined peptides with a biological        sample that comprises albumin or a fragment thereof and        detecting the binding of said peptide to said albumin or said        albumin fragment.

In some embodiments, the invention relates to a binding means specificfor the above defined peptides, wherein the binding means is anantibody, polyclonal or monoclonal or binding fragment thereof, such asfunctional fragments such as a single domain antibody such as theantibody may be a monoclonal antibody and the binding fragment may be amonoclonal antibody binding fragment.

In some embodiments, the invention relates to an aptamer that isspecific for a peptide which comprises at least one of the sequences ofTables 1-4 (SEQ ID NOs: 183-184, and 188-246), such as the aptamer isspecific for the peptide of the sequence VFDEFKPLVEEPQNLIK (SEQ ID NO:185). The aptamer may for example be a DNA or a peptide aptamer.

In some embodiments, the invention relates to a method of inhibitingimmunosuppression in a patient in need thereof, said method comprising:

-   -   identifying a patient having a condition associated with        immunosuppression;    -   administering to the patient any of the above defined peptides        and    -   detecting an increase in leukocyte spreading in the patient. The        peptide may be less than or equal to 50, 49, 48, 47, 46, 45, 44,        43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28,        27, 26, 25, 24, 23, 22, 21, 20, 19, 16, 15, 14, 13, 12, 11, 10,        9, 8, 7, 6 or 5 amino acids in length or any length in between        any of these numbers and the peptide may be synthetic.        Administering of said peptide may comprise administering a        composition consisting of at least 0.1% of the peptide by        weight, for example, at least 0.1%, 0.2%, 0.5%, 1%, 2%, 3%, 4%,        5%, 6%, 7%, 8%, 9%, 10%, 20%, or 30% of the peptide by weight,        including ranges between any two of the listed values. Said        patient may suffer from cancer, a viral infection, or a        bacterial infection, such as said cancer may be colorectal        cancer, renal cancer, breast cancer, skin cancer, ovarian        cancer, prostate cancer, pancreatic, lung, or hematopoietic cell        cancer. The method may further comprise detecting an increase in        lymphocyte migration.

In some embodiments the invention relates to a method of inhibitingbinding of an albumin fragment to a receptor, the method comprising:

-   -   identifying a human suffering from immunosuppression;    -   contacting an immune cell with any of the peptides defined        above; and    -   detecting an increase in proliferation of the immune cell after        contact with said peptide. The immune cell may for example be a        lymphocyte or PBMC. The human may suffer from cancer, a viral        infection, or a bacterial infection, such as said cancer may be        colorectal cancer, renal cancer, breast cancer, skin cancer,        ovarian cancer, prostate cancer, pancreatic, lung, or        hematopoietic cell cancer.

In some embodiments the invention relates to a method of increasingNK-cell cytotoxicity comprising:

-   -   identifying a human suffering from immunosuppression;    -   contacting NK-cells with the any of the above defied peptides;        and    -   detecting an increase in cytotoxicity of said NK-cells after        contact with said peptide as compared to a control sample, such        as the cytotoxicity of NK-cells in the absence of said peptide        or the cytotoxicity of NK-cells and an unrelated peptide. The        human may suffer from cancer, a viral infection, or a bacterial        infection, such as said cancer may be colorectal cancer, renal        cancer, breast cancer, skin cancer, ovarian cancer, prostate        cancer, pancreatic, lung, or hematopoietic cell cancer.

In some embodiments, the invention relates to a method of increasinghuman lymphocyte migration comprising:

-   -   identifying a human suffering from immunosuppression;    -   contacting human lymphocytes with any of the above defined        peptides; and    -   detecting an increase in migration of said human lymphocytes        after contact with said peptide as compared to a control sample,        such as the migration of human lymphocytes in the absence of        said peptide or the migration of human lymphocytes and an        unrelated peptide. The human may suffer from cancer, a viral        infection, or a bacterial infection, such as said cancer may be        colorectal cancer, renal cancer, breast cancer, skin cancer,        ovarian cancer, prostate cancer, pancreatic, lung, or        hematopoietic cell cancer.

In some embodiments the invention relates to a method of inhibiting thebinding of a human albumin or a human albumin fragment to the LFA-1receptor or the IL-2 receptor or both on human lymphocytes comprising:

-   -   contacting human lymphocytes with any of the above defined        peptides in the presence of human albumin or a human albumin        fragment; and    -   detecting an inhibition of binding of a human albumin or a human        albumin fragment to the LFA-1 receptor or the IL-2 receptor or        both on human lymphocytes as compared to a control sample, such        as the binding of a human albumin or a human albumin fragment to        the LFA-1 receptor or the IL-2 receptor or both on human        lymphocytes in the absence of said peptide or the binding of a        human albumin or a human albumin fragment to the LFA-1 receptor        or the IL-2 receptor or both on human lymphocytes in the        presence of an unrelated peptide. The human albumin fragment        comprises a sequence with at least 95% identity to SEQ ID NO:        185, such as the human albumin fragment comprise the sequence of        SEQ ID NO: 185.

In some embodiments the invention relates to a method of inhibiting thebinding of a human albumin or a human albumin fragment to the LFA-1receptor or the IL-2 receptor or both on human lymphocytes comprising:

-   -   providing human lymphocytes, wherein at least one of the LFA-1        receptor and IL-2 receptor is bound to a human albumin of        albumin fragment;    -   specifically binding a molecule to the human albumin or albumin        fragment; and    -   detecting an decrease of inhibition of stimulation of the human        lymphocytes via the LFA-1 receptor, IL-2 receptor. The human        albumin fragment comprises a sequence with at least 95% identity        to SEQ ID NO: 185, such as the human albumin fragment comprise        the sequence of SEQ ID NO: 185.

In some embodiments, the invention relates to a method of binding cancercells with a peptide comprising:

-   -   contacting cancer cells with any of the above defined peptides;        and    -   detecting the binding of said peptide to said cancer cells. Said        cancer may be colorectal cancer cells, renal cancer cells,        breast cancer cells, skin cancer cells, ovarian cancer cells,        prostate cancer cells, pancreatic cancer cells, lung cancer        cells, renal cancer cells, malignant melanoma cells, or        hematopoietic cancer cells. Said peptide may comprise a        detectable label joined thereto, such as a biotinylated label, a        radioactive label, a fluorescent label, or a colloidal gold        label and/or comprises a cytotoxic agent joined thereto, such as        a radiochemical, or a toxin and/or an antibody or antibody        fragment or functional fragment thereof.

In some embodiments, the invention relates to a method of inhibiting theproliferation of human cancer cells comprising:

-   -   identifying a human cancer patient;    -   contacting immune cells of the human cancer patient with any of        the above defined peptides; and    -   detecting an inhibition of proliferation of cancer cells of the        patient or an induction of cell death of cancer cells of the        patient. An inhibition of proliferation of cancer cells of the        patient may for example be detected and/or an induction of cell        death of cancer cells of the patient may be detected. The cancer        may for example be colorectal cancer cells, renal cancer cells,        breast cancer cells, skin cancer cells, ovarian cancer cells,        prostate cancer cells, pancreatic cancer cells, lung cancer        cells, renal cancer cells, malignant melanoma cells, or        hematopoietic cancer cells. For example an an increase in the        proliferation of immune cells of the human may be detected. The        immune cells may be lymphocytes or PBMC. The peptide use in the        method may be synthetic.

In some embodiments the invention relates to a method of removing aligand bound to the LFA-1 receptor of human lymphocytes comprising:

-   -   contacting human lymphocytes with any of the above defined        peptides; and    -   detecting a reduced binding of a ligand for the LFA-1 receptor.        Said human lymphocytes may be from a patient with cancer, a        bacterial infection or a viral infection such as a patient        suffering from breast cancer, renal cell carcinoma, skin cancer,        ovarian cancer, prostate cancer, pancreatic, lung, or        hematopoietic cell cancer.

In some embodiments, the invention relates to a method of removing aligand bound to the IL-2 receptor of human lymphocytes comprising:

-   -   contacting human lymphocytes with any of the above defined        peptides; and    -   detecting a reduced binding of a ligand for the IL-2 receptor.        Said human lymphocytes may be from a patient with cancer, a        bacterial infection or a viral infection such as a patient        suffering from breast cancer, renal cell carcinoma, skin cancer,        ovarian cancer, prostate cancer, pancreatic, lung, or        hematopoietic cell cancer.

In some embodiments, the invention relates to a method of reducingimmunosuppression in a human that is immunosuppressed comprising:

-   -   providing to a human, a peptide as defined above; and    -   detecting a reduction of immunosupression in said human such as        by detecting an activation or stimulation of an immune cell, as        evidenced by an increase in CD69 or CD71 expression, induction        of the secretion of a signal substance, as evidenced by        interferon gamma or IL-12 production, or stimulation of the        release of a cytolytic substance, as evidenced by the release of        granzyme B or perforin, enhanced cytotoxicity, cytokine        production, cell migration, and/or cell proliferation. Said        human may have cancer, a bacterial infection or a viral        infection, such as said cancer is breast cancer, renal cell        carcinoma, skin cancer, ovarian cancer, prostate cancer,        pancreatic, lung, or hematopoietic cell cancer. Said peptide may        be administered to said human as a composition consisting of at        least at least 0.1% of the peptide by weight, for example, at        least 0.1%, 0.2%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%,        20%, or 30% of the peptide by weight, including ranges between        any two of the listed values. In some embodiments, detection in        immunosuppression comprises detecting one or more of enhanced        cytotoxicity, cytokine production, cell migration, and/or cell        proliferation.

In some embodiments the invention relates to a method of inhibiting thebinding of a human albumin or a human albumin fragment to the LFA-1receptor or the IL-2 receptor or both on human lymphocytes comprising:

-   -   providing a human the polynucleotide or vector as defined above;        and    -   detecting an inhibition of binding of a human albumin or a human        albumin fragment to the LFA-1 receptor or the IL-2 receptor or        both.

In some embodiments, the invention relates to a method of inhibiting theproliferation of human cancer cells comprising:

-   -   providing the polynucleotide or vector as defined above to a        human that has cancer cells; and    -   detecting an inhibition of proliferation of said cancer cells.

In some embodiments, the invention relates to a method of removing aligand bound to the LFA-1 receptor or IL-2 receptor or both of humanlymphocytes comprising:

-   -   contacting human lymphocytes with the polynucleotide or vector        as defined above; and    -   detecting a reduced binding of a ligand for the LFA-1 receptor        or the IL-2 receptor or both.

In some embodiments, the invention relates to a method of reducingimmunosuppression in a human that is immunosuppressed comprising:

-   -   providing the polynucleotide or vector as defined above to said        human; and    -   detecting a reduction of immunosupression in said human such as        by detecting activation or stimulation of an immune cell, as        evidenced by an increase in CD69 or CD71 expression, induction        of the secretion of a signal substance, as evidenced by        interferon gamma or IL-12 production, or stimulation of the        release of a cytolytic substance, as evidenced by the release of        granzyme B or perforin. In some embodiments, detecting a        reduction of immunosuppression comprises detecting one or more        of enhanced cytotoxicity, cytokine production, cell migration,        and/or cell proliferation.

In some embodiments, the invention relates to a pharmaceuticalcomposition comprising:

-   -   any of the above defined peptides; and    -   a pharmaceutically acceptable carrier, excipient, or diluent.        The peptide comprises at least one of SEQ ID NOs: 1-33, 34,        46-53, 62, 64-66, 68, 76, 94-96, 98, 583-586 or 589.

In some embodiments, the invention relates to a method for identifying apatient in need of treatment with an inhibitor of immunoregulatorypeptides or structures, the method comprising:

-   -   contacting immune cells of the patient in vitro with any of the        above defined peptides;    -   detecting an inhibition of proliferation of said immune cells;    -   classifying the patient as likely to respond to treatment with        the inhibitor of immunoregulatory peptides or structures if said        peptide inhibits proliferation of said immune cells. The method        may for example further comprise reducing immunosuppression in        the patient in need, wherein reducing immunosuppression        comprises providing to the patient in need, a peptide as defined        above and/or further comprise detecting a reduction of        immunosupression in said human and/or further comprising        reducing immunosuppression in the patient in need, wherein        reducing immunosuppression comprises providing to the patient in        need, a vector or polynucleotide as defined above and/or further        comprising detecting a reduction of immunosupression in said        human.

In another embodiment the invention relates to an isolated peptide,wherein said peptide comprises an amino acid residue homologous to aminoacid residue K2 of SEQ ID NO: 2 and/or, wherein said peptide comprisesan amino acid residue homologous to amino acid residue K9 of SEQ ID NO:2 and/or, wherein said peptide comprises an amino acid residuehomologous to amino acid residue E15 of SEQ ID NO: 2.

The above defined peptides may comprise at least one modification, forexample at least one non-naturally occurring amino acid and/or comprisesat least one D amino acid, an N-terminal acetyl group, a C-terminalamide group, glycosylation, nitrosylation, a linked pharmacokineticmodifier, or a linked polyethylene glycol Any of the above definedpeptides may have a length being less than or equal to 50, 49, 48, 47,46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29,28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 16, 15, 14, 13, 12, 11, 10, 9,8, 7, 6 or 5 amino acids in length or a length between any two of thesenumbers, such as between 6 amino acids and 20 amino acids in length,between 7 amino acids and 20 amino acids in length preferably between8-16 amino acids in length, and most preferably between 9 and 15 aminoacids in length. Any of the above defined peptides may be joined to asupport as well as multimerized.

In another embodiment the invention relates to an isolatedpolynucleotide comprising a sequence encoding any of the above definedpeptides as well as vectors comprising the isolated polynucleotide aswell as a protein complex comprising albumin or a fragment of albuminbound to any of the above defined peptides. The protein complex may bebound to a support.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising, consisting of or consisting essentially ofFormula (I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166). In some embodiments, thisisolated peptide has a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values. In some embodiments, X is an optional sequence,and can be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ IDNO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ IDNO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ IDNO: 255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ IDNO: 258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO:260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO:263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, Q, or absent. In someembodiments, X₁ is one of FF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT,AL, VF, VM, VS, VV, VT, or VL. In some embodiments, X₂ can be one of LS,LQ, LM, LT, LH, VS, VQ, VM, VT, or VH. In some embodiments, X₃ can beone of LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT,QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST,VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN,LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN,QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN,VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP,LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP,QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP,MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR,LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR,QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR,MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR. In someembodiments, X₄ is an optional sequence, and can be ER, E, or absent. Insome embodiments, if X is absent, X₁ is FF, and X₂ is LS. In someembodiments, the peptide comprises one of SEQ ID NOs: 2-33.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising, consisting of or consisting essentially offormula (II), X₂₀TFFVKLSX₂₁X₂₂ (SEQ ID NO: 173). In some embodiments,this isolated peptide has a length that is less than or equal to 1100amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10,11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28,29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46,47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82,83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100,101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114,115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128,129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160,170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300,320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850,900, 950, 1000, 1050, or 1100 amino acids, including ranges between anytwo of the listed values. In some embodiments, X₂₀ is an optionalsequence, and can be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO: 175), KKGD(SEQ ID NO: 176), KKED (SEQ ID NO: 177), KLD, LD, D, or absent. X₂₁ isan optional sequence, and can be LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT,LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT,VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT,MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN,QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN,VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN,MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP,QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP,VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR(SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR,QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR,VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR,MRR, or absent. In some embodiments, X₂₂ is an optional sequence, andcan be ER, E, or absent.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising, consisting of or consisting essentially ofFormula (III), X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In someembodiments, this isolated peptide has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values. In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, F, or absent. In some embodiments,X₃₁ is an optional sequence, and can be F, S, M, V, T, L, or absent. Insome embodiments, X₃₁ is F. In some embodiments, X₃₂ can be S, Q, M, T,or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M, Q, H, N, P, S, G,A, or R. In some embodiments, X₃₄ is F. X₃₄ is an optional sequence, andcan be R, or absent.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising, consisting of or consisting essentially ofFormula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃ X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀X₇₁₁E X₇₁₂ (SEQ ID NO: 394). In some embodiments, this isolated peptidehas a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues. In some embodiments, X₇₀₀ is an optional sequence, and can be K,A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. In someembodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D, E, F,G, H, I, K, M, N, Q, R, S, T, or V, or absent. In some embodiments, X₇₀₂is an optional sequence, and can be D, A, E, I, V, W, or Y, or absent.In some embodiments, X₇₀₃ is an optional sequence, and can be T, C, M,N, P, Q, R, S, W, or Y, or absent. In some embodiments, X₇₀₄ is anoptional sequence, and can be F, A, I, M, N, P, T, or V, or absent. Insome embodiments, X₇₀₅ is an optional sequence, and can be F, L, M, Q,S, T or V, or absent. In some embodiments, X₇₀₆ is an optional sequence,and can be V, F, G, L, P, R, or absent. In some embodiments, X₇₀₇ is anoptional sequence, and can be L, A, F, G, I, M, N, P, Q, R, S, T, V, orY, or absent. In some embodiments, X₇₀₈ is an optional sequence, and canbe S, H, M, N, Q, or T, or absent. In some embodiments, X₇₀₉ is anoptional sequence, and can be L, A, H, I, M, N, Q, R, S, T, V, or W, orabsent. In some embodiments, X₇₁₀ is an optional sequence, and can be F,A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W, or absent. In someembodiments, X₇₁₁ is an optional sequence, and can be T, F, G, H, I, L,M, N, P, S, V, or W, or absent. In some embodiments, X₇₁₂ is an optionalsequence, and can be R, F, K, N, R, T, or Y, or absent.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising, consisting of or consisting essentially ofFormula (VIII), X₈₀₀K X₈₀₁K X₈₀₂E X₈₀₃ (SEQ ID NO: 395). In someembodiments, this isolated peptide has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values. In some embodiments, X₈₀₀ is anoptional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R, T,V, or K, or absent. In some embodiments, X₈₀₁ is an optional sequence,and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597), EDTFFV (SEQID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO: 600), LDTVFV(SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ ID NO: 603),LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQ ID NO:606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK (SEQ IDNO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611), DDTFFV (SEQID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO: 614), IDTFFV(SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ ID NO: 617),NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQ ID NO:620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV (SEQ IDNO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625), LITFFV (SEQID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO: 628), LYTFFV(SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ ID NO: 631),LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQ ID NO:634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV (SEQ IDNO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639), LDTNFV (SEQID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO: 642), LDTFQV(SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ ID NO: 645),LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQ ID NO:648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV (SEQ IDNO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653), LDTLFV (SEQID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO: 656), LDHFFV(SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ ID NO: 659),LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQ ID NO:662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV (SEQ IDNO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667), LDTFPV (SEQID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO: 670), LDTGFV(SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ ID NO: 673),LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQ ID NO:676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV (SEQ IDNO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681), LDTHFV (SEQID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO: 684), LDLFFV(SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ ID NO: 687),LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQ ID NO:690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV (SEQ IDNO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695), LDTFFQ (SEQID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO: 698), LDKFFV(SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ ID NO: 701),LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQ ID NO:704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN (SEQ IDNO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709), LDTFFD (SEQID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712), TFFV (SEQID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L, or absent.In some embodiments, X₈₀₂ is an optional sequence, and can be LSLFT (SEQID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717), LMLFT (SEQID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720), LSQFT (SEQID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723), LSLMT (SEQID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726), LSLNT (SEQID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729), LSLGT (SEQID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732), LSLFN (SEQID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735), LGLFT (SEQID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738), GSLFT (SEQID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741), NSLFT (SEQID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744), RSLFT (SEQID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747), YSLFT (SEQID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750), LSHFT (SEQID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753), LSRFT (SEQID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756), LSWFT (SEQID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759), LSLLT (SEQID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762), LSLWT (SEQID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765), LSLFH (SEQID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768), LSLFM (SEQID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771), LSLFW (SEQID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774), LSFFT (SEQID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777), LSCFT (SEQID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780), LPLFT (SEQID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783), LDLFT (SEQID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786), WSLFT (SEQID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789), LSPFT (SEQID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792), LILFT (SEQID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795), LSLFY (SEQID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798), LFLFT (SEQID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801), LLLFT (SEQID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804), LSLFE (SEQID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807), LSDFT (SEQID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810), SLFT (SEQID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, or absent. Insome embodiments, X₈₀₃ is an optional sequence, and can be R, F, K, N,R, T, or Y, or absent.

Some embodiments of the invention include compositions that comprise anisolated peptide comprising, consisting of or consisting essentially ofany one or more of the peptides set forth in Table 5.1. In someembodiments, this isolated peptide has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Some embodiments of the invention include compositions that comprise anisolated polynucleotide comprising, consisting of or consistingessentially of isolated polynucleotides encoding a peptide inhibitor(e.g., any one or more of the peptides described above) of analbumin-derived immunoregulatory peptide or structure, as describedherein. Some embodiments include vectors that include such isolatedpolynucleotides. Some embodiments also include protein complexes, whichcomprise an albumin or albumin fragment bound to an inhibitor of one ormore albumin-derived immunoregulatory peptides or structures, asdescribed herein.

In some embodiments, any of the compositions described above comprises abuffer selected from the group consisting of: Trizma, Bicine, Tricine,MOPS, MOPSO, MOBS, Tris, Hepes, HEPBS, MES, phosphate, carbonate,acetate, citrate, glycolate, lactate, borate, ACES, ADA, tartrate, AMP,AMPD, AMPSO, BES, CABS, cacodylate, CHES, DIPSO, EPPS, ethanolamine,glycine, HEPPSO, imidazole, imidazolelactic acid, PIPES, SSC, SSPE,POPSO, TAPS, TABS, TAPSO and TES.

Some embodiments include methods of making the protein complexes asdescribed herein. The methods can include contacting a peptide asdescribe herein with a biological sample from a human. In someembodiments, the biological sample includes an albumin or an albuminfragment. The methods can include detecting the presence of the proteincomplex.

Some embodiments of the invention include methods of detecting thepresence of an albumin or an albumin fragment in a biological sample.The methods can include contacting a peptide inhibitor (e.g., aninhibitor of one or more albumin-derived immunoregulatory peptides orstructures, as described herein) with a biological sample that includesan albumin or an albumin fragment. The methods can include detecting thebinding of the albumin or albumin fragment to the inhibitor of one ormore albumin-derived immunoregulatory peptides or structures, asdescribed herein. Some embodiments of the invention include antibodiesor binding fragment thereof that are specific for one or morealbumin-derived immunoregulatory peptides or structures, as describedherein.

Some embodiments of the invention include aptamers that are specific forand bind to a peptide having the sequence VFDEFKPLVEEPQNLIK (SEQ ID NO:185) or a fragment thereof. Some embodiments of the invention includeaptamers that are specific for and bind to any of the immunoregulatorypeptides described herein (e.g., any one of the peptides described inthe tables provided herein). In some embodiments, the aptamers areoligonucleotide aptamers. In some embodiments, the aptamers are peptideaptamers.

Some embodiments of the invention include methods of addressing apatient suffering from immunosuppression, such as immunosupressionresulting from cancer, or infection by a pathogenic, viral or bacterial,enduring or chronic infections, for example due to antibioticresistance. Such approaches include methods of treatingimmunosuppression or inhibiting an aspect of or marker forimmunosuppression, such as a reduced immune cell proliferation, reducedNK-cell cytotoxicity, or reduced leukocyte migration or methods oftreating a viral or bacterial disease (e.g., methods of treating orinhibiting a chronic viral infection such as hepatitis or a bacterialinfection such as that caused by Staphylococcus, Streptococcus,Psuedomonas, or other pathogenic bacteria. The methods can includeidentifying a patient having a condition associated withimmunosuppression such as cancer or a bacterial or viral infection or anenduring or chronic bacterial or viral infection. The methods caninclude administering to the identified patient one or more of thepeptide inhibitors (e.g., an inhibitor of one or more albumin-derivedimmunoregulatory peptides or structures), as described herein and,optionally, detecting activation or stimulation of an immune cell, asevidenced by an increase in CD69 or CD71 expression, induction of thesecretion of a signal substance, as evidenced by interferon gamma orIL-12 production, stimulation of the release of a cytolytic substance,as evidenced by the release of granzyme B or perforin, enhancedcytotoxicity, cytokine production, cell migration, and/or cellproliferation. The methods can also include detecting an increase inleukocyte spreading in the patient. Some of these methods can include,for example, compositions that comprise an isolated peptide comprising,consisting of or consisting essentially of any one or more of thepeptides set forth in Table 5.1 or 5.4, or a peptide comprising,consisting of, or consisting essentially of SEQ ID NO: 2, 62, 584, or589. In some embodiments, the isolated peptide from Table 5.1 or 5.4used in these methods has a length that is less than or equal to 1100amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10,11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28,29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46,47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82,83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100,101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114,115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128,129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160,170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300,320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850,900, 950, 1000, 1050, or 1100 amino acids, including ranges between anytwo of the listed values.

Some embodiments of the invention include methods of inhibiting bindingof an albumin fragment to a receptor. The methods can includeidentifying a human that has immunosuppression. The methods can includecontacting an immune cell with a peptide (e.g., an inhibitor of one ormore albumin-derived immunoregulatory peptides or structures), asdescribed herein. Serum of the human can be present when the immune cellis contacted with the inhibitor. The methods can include detecting anincrease in proliferation of the immune cell or activation orstimulation of an immune cell, as evidenced by an increase in CD69 orCD71 expression, induction of the secretion of a signal substance, asevidenced by interferon gamma or IL-12 production, or stimulation of therelease of a cytolytic substance, as evidenced by the release ofgranzyme B or perforin after contact with the inhibitor of one or morealbumin-derived immunoregulatory peptides or structures, as describedherein. In some embodiments, the methods comprise detecting one or moreof enhanced cytotoxicity, cytokine production, cell migration, and/orcell proliferation.

Some embodiments of the invention include methods of increasing NK-cellor lymphocyte cytotoxicity in the presence of autologous human serum.The methods can include identifying a human that has immunosuppression.The methods can include contacting NK-cells with a peptide as describedherein (e.g., an inhibitor of one or more albumin-derivedimmunoregulatory peptides or structures) in the presence of serum of thehuman. The methods can include detecting an increase in cytotoxicity ofsaid NK-cells after contact with the inhibitor, as compared to a controlsample. Control samples can include the cytotoxicity of NK-cells in thepresence of autologous human serum in the absence of said inhibitor orthe cytotoxicity of NK-cells in the presence of autologous human serumand an unrelated peptide.

Some embodiments of the invention include methods of increasing humanlymphocyte functions, such as migration in the presence of autologoushuman serum or activation or stimulation of an immune cell, as evidencedby an increase in CD69 or CD71 expression, induction of the secretion ofa signal substance, as evidenced by interferon gamma or IL-12production, or stimulation of the release of a cytolytic substance, asevidenced by the release of granzyme B or perforin, enhancedcytotoxicity, cytokine production, cell migration, and/or cellproliferation. The methods can include identifying a human sufferingfrom immunosuppression. The methods can include contacting humanlymphocytes with a peptide as described herein (e.g., an inhibitor ofone or more albumin-derived immunoregulatory peptides or structures) inthe presence of serum of the human. The methods can include detecting anincrease in migration of said human lymphocytes or activation orstimulation of an immune cell, as evidenced by an increase in CD69 orCD71 expression, induction of the secretion of a signal substance, asevidenced by interferon gamma or IL-12 production, stimulation of therelease of a cytolytic substance, as evidenced by the release ofgranzyme B or perforin, enhanced cytotoxicity, cytokine production, cellmigration, and/or cell proliferation after contact with the inhibitor,as compared to a control sample. Control samples can include themigration of human lymphocytes in the presence of autologous human serumin the absence of the inhibitor or the migration of human lymphocytes inthe presence of autologous human serum and an unrelated peptide. In someembodiments, the methods comprise As detecting enhanced cytotoxicity,cytokine production, cell migration, and/or cell proliferation.

Some embodiments of the invention include methods of inhibiting thebinding of a human albumin or a human albumin fragment to cellreceptors, such as the LFA-1 receptor or the IL-2 receptor or both, onhuman lymphocytes. The methods can include contacting human lymphocyteswith a peptide as describe herein (e.g., an inhibitor of one or morealbumin-derived immunoregulatory peptides or structures) in the presenceof human albumin or a human albumin fragment. The methods can includedetecting an inhibition of binding of a human albumin or a human albuminfragment to the LFA-1 receptor or the IL-2 receptor or both on humanlymphocytes, as compared to a control sample. Control samples caninclude the binding of a human albumin or a human albumin fragment tothe LFA-1 receptor or the IL-2 receptor or both on human lymphocytes inthe absence of said inhibitor or the binding of a human albumin or ahuman albumin fragment to the LFA-1 receptor or the IL-2 receptor orboth on human lymphocytes in the presence of an unrelated peptide.

Some embodiments of the invention include methods of inhibiting thebinding of a human albumin or a human albumin fragment to the LFA-1receptor or the IL-2 receptor or both on human lymphocytes. The methodscan include providing human lymphocytes. In some embodiments, at leastone of the LFA-1 receptor or IL-2 receptor is bound to a human albuminof albumin fragment. The methods can include specifically binding aninhibitor (e.g., an inhibitor of one or more albumin-derivedimmunoregulatory peptides or structures, as described herein) to thehuman albumin or albumin fragment. The methods can include detecting adecrease of inhibition of stimulation of the human lymphocytes via theLFA-1 receptor, IL-2 receptor or activation or stimulation of an immunecell, as evidenced by an increase in CD69 or CD71 expression, inductionof the secretion of a signal substance, as evidenced by interferon gammaor IL-12 production, or stimulation of the release of a cytolyticsubstance, as evidenced by the release of granzyme B or perforin. Insome embodiments, the methods detecting enhanced cytotoxicity, cytokineproduction, cell migration, and/or cell proliferation.

Some embodiments of the invention include methods of binding cancercells with a molecule that specifically interacts with said cancer cells(e.g., an inhibitor of one or more albumin-derived immunoregulatorypeptides or structures, as described herein). The methods can includecontacting cancer cells with one or more of the inhibitors, as describedherein. In some embodiments, the method comprises an ex vivo or in vitromethod. In some embodiments, the method comprises an in vivo method. Insome embodiments, the inhibitor is administered peri-tumorally, or neara tumor of a patient, for example within 10 cm, 9, 8, 7, 6, 5, 4, 3, 2,1, or 0.5 cm of the tumor. In some embodiments, the inhibitor isadministered systemically. In some embodiments, the inhibitor isadministered in conjunction with a second therapeutic agent, for examplea therapeutic agent selected to stimulate an immune cell after an LFA-1receptor of the immune cell has been de-blocked, or a therapeutic agentselected to stimulate an immune cell after an IL-2 receptor of theimmune cell has been de-blocked. The methods can include detecting thebinding of said inhibitor to said cancer cells.

Some embodiments of the invention include methods of inhibiting theproliferation of human cancer cells. The methods can include identifyinga human cancer patient. The methods can include contacting immune cellsof the human cancer patient with an inhibitor (e.g., an inhibitor of oneor more albumin-derived immunoregulatory peptides or structures, asdescribed herein). In some embodiments, the inhibitor is administeredperi-tumorally, or near a tumor of the patient, for example within 10cm, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.5 cm of the tumor. In someembodiments, the inhibitor is administered systemically. In someembodiments, the inhibitor is administered in conjuction with a secondtherapeutic agent, for example a therapeutic agent selected to stimulatean immune cell after an LFA-1 receptor of the immune cell has beende-blocked. The methods can include detecting an inhibition ofproliferation of cancer cells of the patient or an induction ofapoptosis or cell death of cancer cells of the patient. Optionally, themethod can include co-administering at least one additional therapeuticagent, for example a therapeutic agent that stimulates the activation ofimmune cells (e.g. enhanced expression of CD69 and/or CD71, secretion ofIL-12 of IFNγ, or secretion of perforin or granzyme B, enhancedcytotoxicity, cytokine production, cell migration, and/or cellproliferation) directly or indirectly through the LFA-1 receptor. Insome embodiments, the additional therapeutic agent stimulates one ormore of enhanced cytotoxicity, cytokine production, cell migration,and/or cell proliferation.

Some embodiments of the invention include methods of removing a ligandbound to the LFA-1 receptor of human lymphocytes. The methods caninclude contacting human lymphocytes with an inhibitor (e.g., aninhibitor of one or more albumin-derived immunoregulatory peptides orstructures, as described herein). The methods can include detecting areduced binding of a ligand for the LFA-1 receptor.

Some embodiments of the invention include methods of removing a ligandbound to the IL-2 receptor of human lymphocytes. The methods can includecontacting human lymphocytes with an inhibitor (e.g., an inhibitor ofone or more albumin-derived immunoregulatory peptides or structures, asdescribed herein). The methods can include detecting a reduced bindingof a ligand for the IL-2 receptor or detecting activation or stimulationof an immune cell, as evidenced by an increase in CD69 or CD71expression, induction of the secretion of a signal substance, asevidenced by interferon gamma or IL-12 production, or stimulation of therelease of a cytolytic substance, as evidenced by the release ofgranzyme B or perforin. In some embodiments, the methods comprisedetecting one or more of enhanced cytotoxicity, cytokine production,cell migration, and/or cell proliferation.

Some embodiments of the invention include methods of reducingimmunosuppression in a human that is immunosuppressed. The methods caninclude providing to a human, a an inhibitor, as described herein (e.g.,an inhibitor of one or more albumin-derived immunoregulatory peptides orstructures). The methods can include detecting a reduction ofimmunosuppression in the human or detecting activation or stimulation ofan immune cell, as evidenced by an increase in CD69 or CD71 expression,induction of the secretion of a signal substance, as evidenced byinterferon gamma or IL-12 production, or stimulation of the release of acytolytic substance, as evidenced by the release of granzyme B orperforin. In some embodiments, the methods comprise detecting one ormore of enhanced cytotoxicity, cytokine production, cell migration,and/or cell proliferation.

Some embodiments of the invention include methods of inhibiting thebinding of a human albumin or a human albumin fragment to the LFA-1receptor or the IL-2 receptor or both on human lymphocytes. The methodscan include providing a human with one or more of the polynucleotidesand/or vector as described herein (e.g., a polynucleotide or vectorhaving a sequence encoding one or more of the inhibitors of thealbumin-derived immunoregulatory peptides or structures). The methodscan include detecting an inhibition of binding of a human albumin or ahuman albumin fragment to the LFA-1 receptor or the IL-2 receptor orboth or detecting activation or stimulation of an immune cell, asevidenced by an increase in CD69 or CD71 expression, induction of thesecretion of a signal substance, as evidenced by interferon gamma orIL-12 production, or stimulation of the release of a cytolyticsubstance, as evidenced by the release of granzyme B or perforin.Optionally, the method can include detecting one or more of enhancedcytotoxicity, cytokine production, cell migration, and/or cellproliferation. Optionally, the method can include co-administering atleast one additional therapeutic agent, for example a therapeutic agentthat stimulates the activation of immune cells (e.g. enhanced expressionof CD69 and/or CD71, secretion of IL-12 of IFNγ, secretion of perforinor granzyme B, enhanced cytotoxicity, cytokine production, cellmigration, and/or cell proliferation) directly or indirectly through theLFA-1 receptor. The additional therapeutic agent can be administeredconcurrently with, or after the inhibitor. In some embodiments, thesecond therapeutic agent stimulates one or more of enhancedcytotoxicity, cytokine production, cell migration, and/or cellproliferation.

Some embodiments of the invention include methods of inhibiting theproliferation of human cancer cells. The methods can include providing ahuman that has cancer with one or more of the polynucleotides or vectoras described herein (e.g., a polynucleotide or vector having a sequenceencoding one or more of the inhibitors of the albumin-derivedimmunoregulatory peptides or structures). In some embodiments, theinhibitor is administered peri-tumorally, or near a tumor of thepatient, for example within 10 cm, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.5 cmof the tumor. In some embodiments, the inhibitor is administeredsystemically. In some embodiments, the inhibitor is administered inconjuction with a second therapeutic agent, for example a therapeuticagent selected to stimulate an immune cell after an LFA-1 receptor ofthe immune cell has been de-blocked. The methods can include detectingan inhibition of proliferation of said cancer cells or detectingactivation or stimulation of an immune cell, as evidenced by an increasein CD69 or CD71 expression, induction of the secretion of a signalsubstance, as evidenced by interferon gamma or IL-12 production,stimulation of the release of a cytolytic substance, as evidenced by therelease of granzyme B or perforin, enhanced cytotoxicity, cytokineproduction, cell migration, or cell proliferation. In some embodiments,the methods comprise detecting one or more of enhanced cytotoxicity,cytokine production, cell migration, and/or cell proliferation.

Some embodiments of the invention include inducing infiltration of acancer by immune cells. The methods can include administering a peptideinhibitor as described herein peri-tumorally, or near a tumor of apatient, for example within 10 cm, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.5 cmof the tumor. The methods can include detecting an infiltration of thecancer by immune cells.

Some embodiments of the invention include methods of removing a ligandbound to the LFA-1 receptor or IL-2 receptor or both of humanlymphocytes. The methods can include providing a human with one or moreof the polynucleotides or vector as described herein (e.g., apolynucleotide or vector having a sequence encoding one or more of theinhibitors of the albumin-derived immunoregulatory peptides orstructures). The methods can include detecting a reduced binding of aligand for the LFA-1 receptor or the IL-2 receptor or both.

Some embodiments of the invention include methods of reducingimmunosuppression in a human that is immunosuppressed. The methods caninclude providing a human with one or more of the polynucleotides orvector as described herein (e.g., a polynucleotide or vector having asequence encoding one or more of the inhibitors of the albumin-derivedimmunoregulatory peptides or structures). The methods can includedetecting a reduction of immunosuppression in the human such asdetecting activation or stimulation of an immune cell, as evidenced byan increase in CD69 or CD71 expression, induction of the secretion of asignal substance, as evidenced by interferon gamma or IL-12 production,stimulation of the release of a cytolytic substance, as evidenced by therelease of granzyme B or perforin, enhanced cytotoxicity, cytokineproduction, cell migration, and/or cell proliferation. In someembodiments, the methods comprise detecting one or more of enhancedcytotoxicity, cytokine production, cell migration, and/or cellproliferation.

Some embodiments of the invention include pharmaceutical compositions.The pharmaceutical compositions can include one or more of thepolynucleotides or vector as described herein (e.g., a polynucleotide orvector having a sequence encoding one or more of the inhibitors of thealbumin-derived immunoregulatory peptides or structures) and/or one ormore of the inhibitors described herein (e.g., a peptide inhibitor ofone or more albumin-derived immunoregulatory peptides or structures, asdescribed herein). The pharmaceutical compositions can include apharmaceutically acceptable carrier or diluent.

Some embodiments of the invention include methods for identifying apatient in need of inhibition of immunoregulatory peptides. The patientcan have albumin-derived immunoregulatory peptides or structures boundto his or her immune cells, and/or can be likely to respond to treatmentwith an inhibitor of the albumin-derived immunoregulatory peptides orstructures. The diagnostic method can include contacting immune cells ofthe patient in vitro with at least one inhibitor of immunoregulatorypeptides or structures. The diagnostic method can include classifyingthe patient as having immunoregulatory peptides or structures, and/or aslikely to respond to treatment with an inhibitor of immunoregulatorypeptides or structures when the block of immunoregulatory peptides orstructures increases restoration of immune parameters or improves immuneresponse, for example, proliferation or response by the PBMCs of saidsubject. The method can include determining which inhibitor orinhibitors of immunoregulatory peptides have immunomodulatory activityin the patient.

Some embodiments of the invention include an isolated peptide comprisingthe amino acid sequence FFVKLS (SEQ ID NO: 62), wherein the isolatedpeptide comprises no more than 30 amino acid residues. In someembodiments, the isolated peptide comprises no more than 29 amino acidresidues, for example, no more than 28 amino acids residues, 27, 26, 25,24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, or6 amino acid residues or a range defined by any two of these numbers. Insome embodiments, the isolated peptide comprises no more than 16 aminoacid residues. In some embodiments, the isolated peptide comprises nomore than 8 amino acid residues. In some embodiments, the isolatedpeptide consists of or consists essentially of the amino acid sequenceFFVKLS (SEQ ID NO: 62).

Some embodiments of the invention include an isolated peptide comprisingthe amino acid sequence KKLDTFFVKLSLFTER (SEQ ID NO: 2). In someembodiments, the isolated peptide comprises no more than 100 amino acidresidues, for example no more than 99, 90, 80, 70, 60, 50, 40, 30, or 20amino acid residues or a range defined by any two of these numbers. Insome embodiments, the isolated peptide comprises no more than 30 aminoacid residues. In some embodiments, the isolated peptide consists of theamino acid sequence of SEQ ID NO: 2.

Some embodiments of the invention include an isolated peptide comprisingthe amino acid sequence RKLDTFFVKLSLFTERRR (SEQ ID NO: 586). In someembodiments, the isolated peptide comprises no more than 100 amino acidresidues, for example no more than 99, 90, 80, 70, 60, 50, 40, 30, or 20amino acid residues or a range defined by any two of these numbers. Insome embodiments, the isolated peptide comprises no more than 30 aminoacid residues. In some embodiments, the isolated peptide consists of theamino acid sequence of SEQ ID NO: 586.

Some embodiments of the invention include an isolated peptide comprisingthe formula X₁X₂X₃X₄X₅X₆X₇X₈X₉X₁₀X₁₁X₁₂X₁₃X₁₄X₁₅X₁₆X₁₇; in which X₁ isany amino acid or is absent; X₂ is a positively charged amino acid, F,or N; X₃ is any amino acid; X₄ is any amino acid; X₅ is a polaruncharged amino acid, R, Y, or W; X₆ is a hydrophobic or uncharged polaramino acid; X₇ is a hydrophobic or uncharged polar amino acid; X₈ is ahydrophobic, non-aromatic carbon chain amino acid that is not M or F; X₉is a positively charged amino acid, T, Q, or Y; X₁₀ is any amino acidthat is not negatively charged; X₁₁ is a polar uncharged amino acid orH; X₁₂ is any amino acid that is not negatively charged; X₁₃ is anyamino acid that is not negatively charged; X₁₄ is any amino acid that isnot negatively charged; X₁₅ is a negatively charged amino acid, Y, or Q;X₁₆ is any amino acid that is not negatively charged; and X₁₇ is one ormore positively charged amino acids or is absent. Optionally X₁comprises a positively charged amino acid. In some embodiments, X₁ is Ror K. In some embodiments, X₁₇ is RR. In some embodiments, X₁ is R andX₁₇ is RR. In some embodiments, X₁ comprises R, and X₁₇ comprises RR. Insome embodiments, the peptide is soluble in an aqueous solution. In someembodiments, the peptide is soluble in an aqueous solution. In someembodiments, at least one of: X₁ is K; X₂ is K; X₃ is L; X₄ is D; X₅ isT; X₆ is F; X₇ is F; X₈ is V; X₉ is K; X₁₀ is L; X₁₁ is S; X₁₂ is L; X₁₃is F; X₁₄ is T; X₁₅ is E; or X₁₆ is R. In some embodiments, the isolatedpeptide comprises the amino acid sequence KKLDTFFVKLSLFTER (SEQ ID NO:2). In some embodiments, the isolated peptide comprises the amino acidsequence RKLDTFFVKLSLFTERRR (SEQ ID NO: 586). In some embodiments, theisolated peptide has a length of 30 amino acid residues or less, forexample no more than about 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20,19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, or 6 amino acidresidues or a range defined by any two of these numbers. In someembodiments, the isolated peptide consists of the formulaX₀X₁X₂X₃X₄X₅X₆X₇X₈X₉X₁₀X₁₁X₁₂X₁₃X₁₄X₁₅X₁₆X₁₇. In some embodiments, theisolated peptide comprises the amino acid sequence KKLDTFFVKLSLFTER (SEQID NO: 2). In some embodiments, the isolated peptide comprises the aminoacid sequence RKLDTFFVKLSLFTERRR (SEQ ID NO: 586).

In some embodiments, any of the above isolated peptides comprises asynthetic peptide.

In some embodiments, any of the above isolated peptides comprises atleast one modification, for example at least one of a D amino acid, anN-terminal acetyl group, a C-terminal amide group, glycosylation,nitrosylation, carbonylation, oxidation, a linked pharmacokineticmodifier, and a linked polyethylene glycol or any combination thereof.

In some embodiments, any of the above isolated peptides activates animmune cell. By way of example, activation of an immune cell can includeproliferation of the immune cell, increased expression of CD69 or CD71,secretion of a signal substance such as IFNγ of IL-12, secretion of acytolytic molecule such as perforin or granzyme B, enhancedcytotoxicity, cytokine production, and/or cell migration.

In some embodiments, any of the above isolated peptides activates animmune cell, if a solution comprising the immune cell comprises a secondpeptide having the sequence VFDEFKPLVEEPQNLIK (SEQ ID NO: 185), or if anLFA-1 receptor of the immune cell is bound to the second peptide.

In some embodiments, if any of the above isolated peptides is contactedwith a second peptide consisting of the amino acid sequenceVFDEFKPLVEEPQNLIK (SEQ ID NO: 185), the isolated peptide specificallybinds to the second peptide.

In some embodiments, if any of the above isolated peptides is contactedwith an immune cell comprising an LFA-1 receptor and a second peptideconsisting of the amino acid sequence VFDEFKPLVEEPQNLIK (SEQ ID NO:185), the isolated peptide inhibits binding of the second peptide to theLFA-1 receptor.

Some embodiments of the invention include a composition comprising anyof the isolated peptides described above and a pharmaceuticallyacceptable carrier or diluent. In some embodiments, the pharmaceuticallyacceptable carrier or diluent comprises a degradable particle. In someembodiments, the composition comprises an amount of the peptide that isat least about 1 ng of the peptide, for example at least about 1 ng, 2ng, 3 ng, 4 ng, 5 ng, 10 ng, 20 ng, 50 ng, 60 ng, 70 ng, 80 ng, 90 ng,100 ng, 200 ng, 300 ng, 400 ng, 500 ng, 600 ng, 700 ng, 800 ng, 900 ng,about 1 μg, 2 μg, 3 μg, 4 μg, 5 μg, 6 μg, 7 μg, 8 μg, 9 μg, 10 μg, 20μg, 30 μg, 40 μg, 50 μg, 60 μg, 70 μg, 80 μg, 90 μg, 100 μg, or 200 μgor a range defined by any two of these numbers. In some embodiments, thecomposition comprises a buffer selected from the group consisting of:Trizma, Bicine, Tricine, MOPS, MOPSO, MOBS, Tris, Hepes, HEPBS, MES,phosphate, carbonate, acetate, citrate, glycolate, lactate, borate,ACES, ADA, tartrate, AMP, AMPD, AMPSO, BES, CABS, cacodylate, CHES,DIPSO, EPPS, ethanolamine, glycine, HEPPSO, imidazole, imidazolelacticacid, PIPES, SSC, SSPE, POPSO, TAPS, TABS, TAPSO and TES. In someembodiments, if contacted with a cancer cell, the composition inducescytotoxicity of the cancer cell. In some embodiments, the cancer cellcomprises a prostate cancer cell. In some embodiments, the compositioncomprises a gel. In some embodiments, the composition will remain in agel format for at least 72 hours under physiological conditions.

Some embodiments of the invention include a method comprisingadministering to an individual having a cancer, and in need of treatmenttherefor, an effective amount of any of the compositions describedabove, thereby inducing at least one of the following: (a) activation ofan immune cell (e.g. enhanced expression of CD69 and/or CD71, secretionof IL-12 of IFNγ, or secretion of perforin or granzyme B, enhancedcytotoxicity, cytokine production, cell migration, and/or cellproliferation); (b) inhibition of binding of a damaged albumin, anaggregate of albumins, an albumin fragment, or a second peptide to anLFA-1 receptor or IL-2 receptor, wherein the second peptide or albuminfragment, if present, comprises at least one of SEQ ID NOs: 183-246; or(c) cytotoxicity to the tumor cell. In some embodiments, (a) and (b) areinduced. In some embodiments, (a), (b), and (c) are induced. In someembodiments, the receptor comprises an LFA-1 receptor. In someembodiments, the receptor comprises an IL-2 receptor. In someembodiments, the albumin fragment or second peptide comprises no morethan 100 amino acid residues. In some embodiments, the albumin fragmentor second peptide comprises SEQ ID NO: 185. In some embodiments, thealbumin fragment or second peptide consists of SEQ ID NO: 185. In someembodiments, the LFA-1 receptor is available for stimulation followinginhibition of binding of the albumin, albumin fragment, or secondpeptide. In some embodiments, the immune cell is stimulated followinginhibition of binding of the albumin, albumin fragment, or secondpeptide. In some embodiments, the immune cell is stimulated by a secondtherapeutic agent. In some embodiments, the second therapeutic agent isadministered concurrently with the composition. In some embodiments, thecomposition comprises the second therapeutic agent. In some embodiments,the second therapeutic agent is administered prior to administering thecomposition. In some embodiments, the second therapeutic agent isadministered subsequent to administering the composition. In someembodiments, the peptide of the composition is administered to theindividual at a dose of at least about 0.1 mg/kg, for example at leastabout 0.2 mg/kg, 0.3 mg/kg, 0.4 mg/kg, 0.5 mg/kg, 0.9 mg/kg, 1 mg/kg, 2mg/kg, 3 mg/kg, 5 mg/kg, of 10 mg/kg or a range defined by any two ofthese values. In some embodiments, the peptide of the composition isadministered in at least a first administration and a secondadministration at least five days after the first administration. Insome embodiments, the peptide is administered to a tissue within about10 cm of a tumor of the cancer. In some embodiments, the peptide isadministered peri-tumorally to a tumor of the cancer. In someembodiments, the cancer comprises at least one of colorectal cancer,renal cancer, breast cancer, skin cancer, ovarian cancer, prostatecancer, pancreatic cancer, lung cancer, malignant melanoma, small celllung cancer, non-small lung cancer (adenocarcinoma), squamous cellcarcinoma, bladder cancer, osteosarcoma, bronchial cancer, orhematopoietic cell cancer. In some embodiments, the individual comprisesserum comprising a damaged albumin, an aggregate of albumins, an albuminfragment, or a second peptide, wherein the albumin fragment or secondpeptide comprises at least one of SEQ ID NOs: 183-246. In someembodiments, the second peptide or albumin fragment comprising the aminoacid sequence VFDEFKPLVEEPQNLIK (SEQ ID NO: 185). In some embodiments,the second peptide or albumin fragment comprises no more than 100 aminoacid residues.

Some embodiments of the invention include a method of activating animmune cell (e.g. enhanced expression of CD69 and/or CD71, secretion ofIL-12 of IFNγ, or secretion of perforin or granzyme B, enhancedcytotoxicity, cytokine production, and/or cell migration) in a cancerpatient, the method comprising contacting the immune cell with anisolated peptide comprising the amino acid sequence FFVKLS (SEQ ID NO:62), wherein the peptide consists of about six to thirty amino acids. Insome embodiments, contacting the immune cell with the isolated peptideinhibits binding of a damaged albumin, an aggregate of albumins, analbumin fragment, or a second peptide to an LFA-1 receptor, wherein thealbumin fragment or second peptide comprises at least one of SEQ ID NOs:183-246. In some embodiments, the albumin fragment or second peptidecomprises no more than 100 amino acids. In some embodiments, the albuminfragment or second peptide comprises SEQ ID NO: 185. In someembodiments, the albumin fragment or second peptide consists of SEQ IDNO: 185. In some embodiments, the LFA-1 receptor is available forstimulation following inhibition of binding of the albumin, albuminfragment, or second peptide. In some embodiments, the immune cell isstimulated following inhibition of binding of the albumin, albuminfragment, or second peptide. In some embodiments, the immune cell isstimulated by a second therapeutic agent. In some embodiments, thesecond therapeutic agent is administered concurrently with thecomposition. In some embodiments, the composition comprises the secondtherapeutic agent. In some embodiments, the second therapeutic agent isadministered prior to administration of the composition. In someembodiments, the second therapeutic agent is administered subsequent toadministration of the composition.

Some embodiments of the invention include a method of binding cancercells with a peptide. The method can comprise contacting a cancer cellwith any of the peptides described above, and detecting the binding ofsaid peptide to said cancer cell. In some embodiments, the peptidecomprises a detectable moiety. In some embodiments, the detectablemoiety comprises a biotinylated label, a radioactive label, afluorescent label, an enzyme, or a colloidal gold label. In someembodiments, the cancer cell is a colorectal cancer cell, a renal cancercell, a breast cancer cell, a skin cancer cell, an ovarian cancer cell,a prostate cancer cell, a pancreatic cancer cell, a lung cancer cell, amalignant melanoma cell, a small cell lung cancer cell, a non-small lungcancer (adenocarcinoma) cell, a squamous cell carcinoma cell, a bladdercancer cell, an osteosarcoma cell, a bronchial cancer cell, or ahematopoietic cell cancer cell. In some embodiments, said peptidecomprises an antibody or antibody fragment.

Some embodiments of the invention include a method of amelioratingimmunosuppression in a subject in need thereof, the method comprisingadministering to the subject an effective amount of the composition ofany of claims 29-36, thereby inducing at least one of the following: (a)activation of an immune cell (e.g. enhanced expression of CD69 and/orCD71, secretion of IL-12 of IFNγ, or secretion of perforin or granzymeB, enhanced cytotoxicity, cytokine production, and/or cell migration);or (b) inhibition of binding of a damaged albumin, an aggregate ofalbumins, an albumin fragment, or a second peptide to an LFA-1 receptor,wherein the second peptide or albumin fragment, if present, comprises atleast one of SEQ ID NOs: 183-246. In some embodiments, the albuminfragment or second peptide comprises no more than 100 amino acidresidues. In some embodiments, the albumin fragment or second peptidecomprises SEQ ID NO: 185. In some embodiments, the albumin fragment orsecond peptide consists of SEQ ID NO: 185. In some embodiments, theLFA-1 receptor is available for stimulation following inhibition ofbinding of the albumin, albumin fragment, or second peptide.

Some embodiments include a kit comprising the isolated peptide of anyone of claims 1-26; and a detectable label. In some embodiments, thelabel comprises a biotinylated label, a radioactive label, a fluorescentlabel, an enzyme, or a colloidal gold label.

Some embodiments include an isolated nucleic acid encoding any of theisolated peptides described above. Some embodiments include an isolatedvector comprising this nucleic acid.

Some embodiments of the invention include use of any of the isolatedpeptides described above for the preparation of a medicament for thetreatment of cancer.

Some embodiments of the invention include use of any of the isolatedpeptides described above for the preparation of a medicament forstimulating an immune cell in a cancer patient.

Some embodiments of the invention include use of any of the compositionsdescribed above for the preparation of a medicament for the treatment ofcancer.

Some embodiments of the invention include use of any of the compositionsdescribed above for the preparation of a medicament for stimulating animmune cell in a cancer patient.

In some embodiments, for any of the uses described above, the cancercomprises at least one of colorectal cancer, renal cancer, breastcancer, skin cancer, ovarian cancer, prostate cancer, pancreatic cancer,lung cancer, malignant melanoma, small cell lung cancer, non-small lungcancer (adenocarcinoma), squamous cell carcinoma, bladder cancer,osteosarcoma, bronchial cancer, or hematopoietic cell cancer.

Some embodiments of the invention include use of any of the isolatedpeptides described above for the preparation of a medicament for thetreatment of immunosuppression.

Some embodiments of the invention include use of any of the compositionsdescribed above for the preparation of a medicament for the treatment ofimmunosuppression.

A number of Alternatives are also provided herein:

Alternative 1 includes an isolated peptide comprising Formula VIIwherein Formula VII is: X₇₀₀KX₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆KX₇₀₇X₇₀₈X₇₀₉X₇₁₀X₇₁₁EX₇₁₂ (SEQ ID NO: 394),wherein X₇₀₀ is K, A, D, E, G, H, I, L, M, N, P, Q, R, T, V, or K, orabsent; wherein X₇₀₁ is L, A, C, D, E, F, G, H, I, K, M, N, Q, R, S, T,or V, or absent; wherein X₇₀₂ is D, A, E, I, V, W, or Y, or absent;wherein X₇₀₃ is T, C, M, N, P, Q, R, S, W, or Y, or absent; wherein X₇₀₄is F, A, I, M, N, P, T, or V, or absent; wherein X₇₀₅ is F, L, M, Q, S,T or V, or absent; wherein X₇₀₆ is V, F, G, L, P, or R, or absent;wherein X₇₀₇ is L, A, F, G, I, M, N, P, Q, R, S, T, V, or Y, or absent;wherein X₇₀₈ is S, H, M, N, Q, or T, or absent; wherein X₇₀₉ is L, A, H,I, M, N, Q, R, S, T, V, or W, or absent; wherein X₇₁₀ is F, A, C, G, H,I, L, M, NP, Q, R, S, T, V, or W, or absent; wherein X₇₁₁ is T, F, G, H,I, L, M, N, P, S, V, or W, or absent; and wherein X₇₁₂ is R, F, K, N, R,T, or Y, or absent.

Alternative 2 includes the isolated peptide of Alternative 1, whereinsaid Formula VII is one of SEQ ID NO: 1-101, 167-172, 174-177, 179-393,396-581, or 582.

Alternative 3 includes an isolated peptide comprising Formula VIII,wherein Formula VIII is: X₈₀₀K X₈₀₁K X₈₀₂E X₈₀₃ (SEQ ID NO: 395),wherein X₈₀₀ is K, A, D, E, G, H, I, L, M, N, P, Q, R, T, V, or K, orabsent; wherein X₈₀₁ is LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO:597), EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ IDNO: 600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQID NO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV(SEQ ID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608),LDTFFK (SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO:611), DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ IDNO: 614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQID NO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV(SEQ ID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622),VDTFFV (SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO:625), LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ IDNO: 628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQID NO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV(SEQ ID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636),LDYFFV (SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO:639), LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ IDNO: 642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQID NO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR(SEQ ID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650),LDTFAV (SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO:653), LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ IDNO: 656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQID NO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV(SEQ ID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664),LDTYFV (SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO:667), LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ IDNO: 670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQID NO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV(SEQ ID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678),LDTKFV (SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO:681), LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ IDNO: 684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQID NO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT(SEQ ID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692),LDIFFV (SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO:695), LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ IDNO: 698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQID NO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS(SEQ ID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706),LDTFFN (SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO:709), LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO:712), TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV,or L, or absent; wherein X₈₀₂ is LSLFT (SEQ ID NO: 715), VSLFT (SEQ IDNO: 716), LQLFT (SEQ ID NO: 717), LMLFT (SEQ ID NO: 718), LTLFT (SEQ IDNO: 719), LHLFT (SEQ ID NO: 720), LSQFT (SEQ ID NO: 721), LSVFT (SEQ IDNO: 722), LSMFT (SEQ ID NO: 723), LSLMT (SEQ ID NO: 724), LSLQT (SEQ IDNO: 725), LSLHT (SEQ ID NO: 726), LSLNT (SEQ ID NO: 727), LSLPT (SEQ IDNO: 728), LSLST (SEQ ID NO: 729), LSLGT (SEQ ID NO: 730), LSLAT (SEQ IDNO: 731), LSLRT (SEQ ID NO: 732), LSLFN (SEQ ID NO: 733), LSLFP (SEQ IDNO: 734), LSLFR (SEQ ID NO: 735), LGLFT (SEQ ID NO: 736), ASLFT (SEQ IDNO: 737), FSLFT (SEQ ID NO: 738), GSLFT (SEQ ID NO: 739), ISLFT (SEQ IDNO: 740), MSLFT (SEQ ID NO: 741), NSLFT (SEQ ID NO: 742), PSLFT (SEQ IDNO: 743), QSLFT (SEQ ID NO: 744), RSLFT (SEQ ID NO: 745), SSLFT (SEQ IDNO: 746), TSLFT (SEQ ID NO: 747), YSLFT (SEQ ID NO: 748), LNLFT (SEQ IDNO: 749), LSAFT (SEQ ID NO: 750), LSHFT (SEQ ID NO: 751), LSIFT (SEQ IDNO: 752), LSNFT (SEQ ID NO: 753), LSRFT (SEQ ID NO: 754), LSSFT (SEQ IDNO: 755), LSTFT (SEQ ID NO: 756), LSWFT (SEQ ID NO: 757), LSLCT (SEQ IDNO: 758), LSLIT (SEQ ID NO: 759), LSLLT (SEQ ID NO: 760), LSLTT (SEQ IDNO: 761), LSLVT (SEQ ID NO: 762), LSLWT (SEQ ID NO: 763), LSLFF (SEQ IDNO: 764), LSLFG (SEQ ID NO: 765), LSLFH (SEQ ID NO: 766), LSLFI (SEQ IDNO: 767), LSLFL (SEQ ID NO: 768), LSLFM (SEQ ID NO: 769), LSLFS (SEQ IDNO: 770), LSLFV (SEQ ID NO: 771), LSLFW (SEQ ID NO: 772), LYLFT (SEQ IDNO: 773), LVLFT (SEQ ID NO: 774), LSFFT (SEQ ID NO: 775), LSGFT (SEQ IDNO: 776), LSKFT (SEQ ID NO: 777), LSCFT (SEQ ID NO: 778), LCLFT (SEQ IDNO: 779), LRLFT (SEQ ID NO: 780), LPLFT (SEQ ID NO: 781), LWLFT (SEQ IDNO: 782), LKLFT (SEQ ID NO: 783), LDLFT (SEQ ID NO: 784), LSYFT (SEQ IDNO: 785), LALFT (SEQ ID NO: 786), WSLFT (SEQ ID NO: 787), LSLFA (SEQ IDNO: 788), LSLFQ (SEQ ID NO: 789), LSPFT (SEQ ID NO: 790), HSLFT (SEQ IDNO: 791), LSLYT (SEQ ID NO: 792), LILFT (SEQ ID NO: 793), KSLFT (SEQ IDNO: 794), CSLFT (SEQ ID NO: 795), LSLFY (SEQ ID NO: 796), LSLFK (SEQ IDNO: 797), LSLFC (SEQ ID NO: 798), LFLFT (SEQ ID NO: 799), LELFT (SEQ IDNO: 800), LSLKT (SEQ ID NO: 801), LLLFT (SEQ ID NO: 802), LSLFD (SEQ IDNO: 803), LSLDT (SEQ ID NO: 804), LSLFE (SEQ ID NO: 805), DSLFT (SEQ IDNO: 806), LSLET (SEQ ID NO: 807), LSDFT (SEQ ID NO: 808), LSEFT (SEQ IDNO: 809), ESLFT (SEQ ID NO: 810), SLFT (SEQ ID NO: 811), LSFT (SEQ IDNO: 812), LFT, LSL, LT, or T, or absent.

Alternative 4 includes the isolated peptide of Alternative 3, whereinsaid formula VIII is one of SEQ ID NOs: 1-34, 64-68, 70-72, 74-77, 80,83, 86, 89, 92-96, 99-100, 264, 268-269, 270-386, 388-393, 396-401, 403,404, 406, 408-411, 413-416, 419-420, 422-438, 442-444, 446-449, 451-453,455-458, 460, 462-466, 470, 472-477, 479-480, 482-484, 486, 487, 489,491-493, 495-498, 500-508, 512-517, 519-522, 528-530, 532, 533, 535-538,540, 542-551, 553, 557-559, 567, 570, 572-581, or 582.

Alternative 5 includes an isolated peptide comprising Formula I, whereinFormula I is: XX₁VKX₂X₃X₄ (SEQ ID NO: 166), wherein X is KKLDT (SEQ IDNO: 167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ IDNO: 170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ IDNO: 253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ IDNO: 256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO: 258), KLDT (SEQ IDNO: 172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO:261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ,EDT, EDQ, DT, DQ, T, Q, or absent, wherein X₁ is FF, FM, FS, FV, FT, FL,AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, or VL, or absent, wherein X₂is LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH, or absent, wherein X₃ isLFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT,QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT,VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN,LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN,QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN,MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP,LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP,QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP,MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR,LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR,QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR,MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR; and wherein X₄ is ER, E,or absent.

Alternative 6 includes the isolated peptide of Alternative 5, whereinsaid Formula I is one of SEQ ID NOs: 2-40, 46-52, 58-65, 67-71, 74-77,80-83, 86-88, 92-96, 99-101, 166, 173, 178, 182, 268-325, 332-392-393,396-415, 417-444, 446-468, 470-487, 489-494, 497-508, 510, 512, 514-517,520-522, 524-525, 528-533, 535-536, 538-539, 542-544, 546, 548, 551,553, 556-559, 561, 563-568, 571-573, 575-581 or 582.

Alternative 7 includes the isolated peptide of Alternative 5, whereinsaid Formula I is one of SEQ ID NOs: 2 to 33.

Alternative 8 an isolated peptide comprising Formula II, wherein FormulaII is XTFFVKLSX₁X₂(SEQ ID NO: 173), wherein X is KKLD (SEQ ID NO: 174),RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO: 177),KLD, LD, D, or absent, wherein X₁ is LFT, LMT, LQT, LHT, LNT, LPT, LST,LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT,VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT,MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN,LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN,VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN,MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP,QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP,VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP,MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR,QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR,VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR,MAR, or MRR, or absent, and wherein X₂ is ER, or E, or absent.

Alternative 9 includes the isolated peptide of Alternative 8, whereinsaid Formula II is one of SEQ ID No: 2-5, 19-38, 46-49, 58-61, 64,68-70, 75, 81, 87, 93, 94, 100, 101, 173, 268-303, 350-393, 396, 398,399, 400, 402, 403, 405, 406-408, 412-414, 417, 418, 421-423, 426-428,430, 431, 435, 436, 438, 439, 440-442, 448-455, 458, 459, 461, 465, 467,468, 471, 475, 476, 478-481, 483, 485, 487, 489-491, 493, 494, 497-499,503, 507, 510, 512, 514-517, 520, 521, 524, 525, 528, 529, 531, 533,538, 539, 542-, 544, 546, 551, 556-559, 561, 563-568, 571-573, 575-577,579, 580, or 581.

Alternative 10 includes the isolated peptide of Alternative 8, wherein Xis KKLD (SEQ ID NO: 174).

Alternative 11 includes the isolated peptide of Alternative 8, whereinX₂ is ER.

Alternative 12 includes the isolated peptide of Alternative 8, whereinsaid formula is TFFVKLSLFTER (SEQ ID NO: 49) or TFFVKLSLFTE (SEQ ID NO:250).

Alternative 13 includes the isolated peptide of Alternative 8, whereinsaid formula is KKLDTFFVKLSLFTER (SEQ ID NO: 2) or KKLDTFFVKLSLFTE (SEQID NO: 34).

Alternative 14 includes an isolated peptide comprising Formula III,wherein Formula III is: XX₁VKLX₂LX₃TEX₄ (SEQ ID NO: 178), wherein X isKKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO: 180), LDTF (SEQ ID NO: 181),DTF, TF, or F, or absent, wherein X₁ is F, M, S, V, T, or L, or absent,wherein X₂ is S, Q, M, T, or H, or absent, wherein X₃ is F, M, Q, H, N,P, S, G, A, or R, or absent, and wherein X₄ is R or absent.

Alternative 15 includes the isolated peptide of Alternative 14, whereinsaid Formula III is one of SEQ ID No: 2-13, 15-18, 22-30, 34, 46-52, 58,64, 65, 70, 71, 76, 77, 82, 83, 88, 93-96, 99, 100, 178, 268-325.

Alternative 16 includes the isolated peptide of Alternative 14, whereinX is KKLDTF (SEQ ID NO: 178).

Alternative 17 includes the isolated peptide of Alternative 14, whereinX₄ is R.

Alternative 18 includes the isolated peptide of Alternative 14, whereinsaid formula is VKLSLFTER (SEQ ID NO: 52) or VKLSLFTE (SEQ ID NO: 251).

Alternative 19 includes the isolated peptide of Alternative 14, whereinsaid formula is KKLDTFFVKLSLFTER (SEQ ID NO: 2) or KKLDTFFVKLSLFTE (SEQID NO: 34).

Alternative 20 includes an isolated peptide comprising at least one ofSEQ ID NOs: 1-101, 167-172, 174-177, 179-393, 396-581 and 582.

Alternative 21 includes the isolated peptide of Alternative 20,comprising at least one of SEQ ID NOs: 1-32, 34, 64-66, 68, 76, 94-96,98, and 264-393.

Alternative 22 includes the isolated peptide of any one of Alternatives1 to 21, wherein the isolated peptide comprises at least one of thesequences of Table 5.1.

Alternative 23 includes the isolated peptide of anyone of Alternatives 1to 22, wherein at least one amino acid is a D amino acid, artificialamino acid, and chemically modified amino acid.

Alternative 24 includes the isolated peptide of anyone of Alternatives 1to 23, further comprising an N-terminal acetyl group.

Alternative 25 includes the isolated peptide of anyone of Alternatives 1to 24, further comprising a C-terminal amide group.

Alternative 26 includes the isolated peptide of anyone of Alternatives 1to 25, wherein said isolated peptide is chemically modified.

Alternative 27 includes the isolated peptide of anyone of Alternatives 1to 26, wherein said peptide comprises at least one modification, forexample wherein the peptide is glycosylated, nitrosylated, carbonylated,oxidized, or joined to at least one of polyethylene glycol, a fattyacid, or a pharmacokinetic modifier.

Alternative 28 includes the isolated polypeptide of anyone ofAlternative 1 to 23 wherein the polypeptide comprises a cyclic peptide.

Alternative 29 includes the isolated peptide of any one of Alternatives1 to 28, wherein said peptide comprises at least one modification, forexample at least one of a D amino acid, an N-terminal acetyl group, aC-terminal amide group, glycosylation, nitrosylation, carbonylation,oxidation, a linked pharmacokinetic modifier, and a linked polyethyleneglycol or any combination thereof.

Alternative 30 includes the isolated peptide of any one of Alternatives1 to 29, wherein said peptide is less than or equal to 1100 amino acidsin length.

Alternative 31 includes the isolated peptide of anyone of Alternatives 1to 29, wherein said peptide is between 6 amino acids and 20 amino acidsin length.

Alternative 32 includes the isolated peptide of anyone of Alternatives 1to 31, wherein the isolated peptide does not have an N-terminal acetylgroup.

Alternative 33 includes the isolated peptide of anyone of Alternatives 1to 31, wherein the isolated peptide does not have a C-terminal amidegroup.

Alternative 34 includes the isolated peptide of anyone of Alternatives 1to 33, wherein said peptide is joined to at least one of a support, acarrier, and a fusion protein.

Alternative 35 includes the isolated peptide of anyone of Alternatives 1to 34, wherein said peptide is multimerized.

Alternative 36 includes an isolated polynucleotide comprising a sequenceencoding the peptide of any one of Alternatives 1 to 22.

Alternative 37 includes the isolated polynucleotide of Alternative 36comprising one of SEQ ID NOs: 102 to 165.

Alternative 38 includes a vector comprising the isolated polynucleotideof Alternative 36.

Alternative 39 includes a vector comprising the isolated polynucleotideof Alternative 37.

Alternative 40 includes the isolated polynucleotide of Alternative 36 or37 or the vector of Alternative 38 or 39, wherein said peptide is lessthan or equal to 1100 amino acids in length.

Alternative 41 includes the isolated polynucleotide of Alternative 36 or37 or the vector of Alternative 38 or 39, wherein said peptide isbetween 6 amino acids and 20 amino acids in length.

Alternative 42 includes a protein complex comprising the peptide ofanyone of Alternatives 1 to 35 bound to at least one of albumin, afragment of albumin, an immunoglobulin, a support, a carrier, and afusion protein.

Alternative 43 includes a method of making a protein complex accordingto Alternative 42, comprising: contacting the peptide of anyone ofAlternatives 1 to 35 with a biological sample obtained from a humansubject, wherein said biological sample comprises immunoglobulin,albumin, or a fragment thereof; and detecting the presence of saidprotein complex.

Alternative 44 includes the method of Alternative 43, wherein saidpeptide of anyone of Alternatives 1 to 35 is attached to a support.

Alternative 45 includes a method of detecting the presence of an albuminor an albumin fragment in a biological sample, the method comprising:contacting the peptide of anyone of Alternatives 1 to 35 with abiological sample that comprises albumin or a fragment thereof anddetecting the binding of said peptide to said albumin or said albuminfragment.

Alternative 46 includes a binding means specific for the peptide of anyone of Alternatives 1 to 35, wherein the binding means is an antibody orbinding fragment thereof.

Alternative 47 includes the binding means of Alternative 46, wherein theantibody is a monoclonal antibody and the binding fragment is amonoclonal antibody binding fragment.

Alternative 48 includes an aptamer that is specific for a peptidecomprising at least one of the sequences of Tables 1-4 (SEQ ID NOs:183-184, and 188-246).

Alternative 49 includes the aptamer of Alternative 48, wherein theaptamer is specific for the peptide of the sequence VFDEFKPLVEEPQNLIK(SEQ ID NO: 185).

Alternative 50 includes the aptamer of Alternative 48 or 49, whereinsaid aptamer is a DNA aptamer.

Alternative 51 includes the aptamer of Alternative 48 or 49, whereinsaid aptamer is a peptide aptamer.

Alternative 52 includes a method of inhibiting immunosuppression in apatient in need thereof, said method comprising: identifying a patienthaving a condition associated with immunosuppression; administering tothe patient a peptide of any of Alternatives 1-35; and detecting anincrease in leukocyte spreading in the patient or detecting activationor stimulation of an immune cell, as evidenced by an increase in CD69 orCD71 expression, induction of the secretion of a signal substance, asevidenced by interferon gamma or IL-12 production, or stimulation of therelease of a cytolytic substance, as evidenced by the release ofgranzyme B or perforin. Optionally the method includes detecting one ormore of enhanced cytotoxicity, cytokine production, cell migration,and/or cell proliferation.

Alternative 53 includes the method of Alternative 52, wherein saidpeptide is less than or equal to 30, 29, 28, 27, 26, 25, 24, 23, 22, 21,20, 19, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, or 6 amino acids in lengthor a length that is between any two of these numbers.

Alternative 54 includes the method of Alternative 52, wherein saidpeptide is a synthetic peptide.

Alternative 55 includes the method of Alternative 52, whereinadministering said peptide comprises administering a compositionconsisting of at least 0.1% of the peptide by weight, for example, atleast 0.1%, 0.2%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20%, or30% of the peptide by weight, including ranges between any two of thelisted values

Alternative 56 includes the method of Alternative 52, wherein saidpatient has cancer, a viral infection, or a bacterial infection.

Alternative 57 includes the method of Alternative 56, wherein the canceris colorectal cancer, renal cancer, breast cancer, skin cancer, ovariancancer, prostate cancer, pancreatic cancer, lung cancer, malignantmelanoma, small cell lung cancer, non-small lung cancer(adenocarcinoma), squamous cell carcinoma, bladder cancer, osteosarcoma,bronchial cancer, or hematopoietic cell cancer.

Alternative 58 includes the method of Alternative 52, further comprisingdetecting an increase in lymphocyte migration.

Alternative 59 includes a method of inhibiting binding of an albuminfragment to a receptor, the method comprising: identifying a humansuffering from immunosuppression; contacting an immune cell with apeptide of any of Alternatives 1 to 35; and detecting an increase inproliferation of the immune cell after contact with said peptide ordetecting activation or stimulation of an immune cell, as evidenced byan increase in CD69 or CD71 expression, induction of the secretion of asignal substance, as evidenced by interferon gamma or IL-12 production,or stimulation of the release of a cytolytic substance, as evidenced bythe release of granzyme B or perforin. Optionally, the method includesone or more of enhanced cytotoxicity, cytokine production, cellmigration, and/or cell proliferation.

Alternative 60 includes the method of Alternative 59, wherein the immunecells is a lymphocyte, monocyte, macrophage, or NK-cell.

Alternative 61 includes the method of Alternative 59, wherein the immunecell is a PBMC, monocyte, macrophage, or NK-cell.

Alternative 62 includes the method of Alternative 59, wherein the humanhas cancer, a viral infection, or a bacterial infection.

Alternative 63 includes the method of Alternative 62, wherein said humanhas colorectal cancer, renal cancer, breast cancer, skin cancer, ovariancancer, prostate cancer, pancreatic cancer, lung cancer, malignantmelanoma, small cell lung cancer, non-small lung cancer(adenocarcinoma), squamous cell carcinoma, bladder cancer, osteosarcoma,bronchial cancer, or hematopoietic cell cancer.

Alternative 64 includes a method of increasing NK-cell cytotoxicitycomprising: identifying a human suffering from immunosuppression;contacting NK-cells with the peptide comprising the sequence of any ofAlternatives 1 to 35; and detecting an increase in cytotoxicity of saidNK-cells after contact with said peptide as compared to a controlsample, such as the cytotoxicity of NK-cells in the absence of saidpeptide or the cytotoxicity of NK-cells and an unrelated peptide.

Alternative 65 includes the method of Alternative 64, wherein said humanis a patient with cancer, a bacterial infection, or a viral infection.

Alternative 66 includes the method of Alternative 64, wherein saidpatient with cancer has colorectal cancer, renal cancer, breast cancer,skin cancer, ovarian cancer, prostate cancer, pancreatic cancer, lungcancer, malignant melanoma, small cell lung cancer, non-small lungcancer (adenocarcinoma), squamous cell carcinoma, bladder cancer,osteosarcoma, bronchial cancer, or hematopoietic cell cancer.

Alternative 67 includes a method of increasing human lymphocytemigration comprising: identifying a human suffering fromimmunosuppression; contacting human lymphocytes with a peptide of any ofAlternatives 1-35; and detecting an increase in migration of said humanlymphocytes after contact with said peptide as compared to a controlsample, such as the migration of human lymphocytes in the absence ofsaid peptide or the migration of human lymphocytes and an unrelatedpeptide.

Alternative 68 includes the method of Alternative 67, wherein said humanhas cancer, a bacterial infection or a viral infection.

Alternative 69 includes the method of Alternative 68, wherein said humanhas at least one of colorectal cancer, renal cancer, breast cancer, skincancer, ovarian cancer, prostate cancer, pancreatic cancer, lung cancer,malignant melanoma, small cell lung cancer, non-small lung cancer(adenocarcinoma), squamous cell carcinoma, bladder cancer, osteosarcoma,bronchial cancer, and hematopoietic cell cancer.

Alternative 70 includes a method of inhibiting the binding of a humanalbumin or a human albumin fragment to the LFA-1 receptor or the IL-2receptor or both on human lymphocytes, the method comprising: contactinghuman lymphocytes with a peptide of any of Alternatives 1-35 in thepresence of human albumin or a human albumin fragment; and detecting aninhibition of binding of the human albumin or human albumin fragment tothe LFA-1 receptor or the IL-2 receptor or both on human lymphocytes ascompared to a control sample, wherein the control sample comprisesbinding of a human albumin or a human albumin fragment to an LFA-1receptor or IL-2 receptor or both on a human lymphocyte in the absenceof said peptide, or binding of a human albumin or a human albuminfragment to an LFA-1 receptor or IL-2 receptor or both on a humanlymphocyte in the presence of an unrelated peptide.

Alternative 71 includes the method of Alternative 70 wherein the humanalbumin fragment comprises a sequence with at least 95% identity to SEQID NO: 185.

Alternative 72 includes the method of Alternative 71, wherein the humanalbumin fragment comprises the sequence of SEQ ID NO: 185.

Alternative 73 includes a method of inhibiting the binding of a humanalbumin or a human albumin fragment to the LFA-1 receptor or the IL-2receptor or both on human lymphocytes comprising: providing humanlymphocytes, wherein at least one of the LFA-1 receptor and IL-2receptor is bound to a human albumin of albumin fragment; specificallybinding a molecule to the human albumin or albumin fragment; anddetecting an decrease of inhibition of stimulation of the humanlymphocytes via the LFA-1 receptor, IL-2 receptor.

Alternative 74 includes the method of Alternative 73 wherein the humanalbumin fragment comprises a sequence with at least 95% identity to SEQID NO: 185.

Alternative 75 includes the method of Alternative 74, wherein the humanalbumin fragment comprises the sequence of SEQ ID NO: 185.

Alternative 76 includes a method of binding cancer cells with a peptidecomprising: contacting a cancer cell with the peptide of any ofAlternatives 1-35; and detecting the binding of said peptide to saidcancer cell.

Alternative 77 includes the method of Alternative 76, wherein the cancercell is a colorectal cancer cell, a renal cancer cell, a breast cancercell, a skin cancer cell, an ovarian cancer cell, a prostate cancercell, a pancreatic cancer cell, a lung cancer cell, a malignant melanomacell, a small cell lung cancer cell, a non-small lung cancer(adenocarcinoma) cell, a squamous cell carcinoma cell, a bladder cancercell, an osteosarcoma cell, a bronchial cancer cell, or a hematopoieticcell cancer cell.

Alternative 78 includes the method of Alternative 76, wherein saidpeptide comprises a detectable label joined thereto, such as abiotinylated label, a radioactive label, a fluorescent label, or acolloidal gold label.

Alternative 79 includes the method of Alternative 76, wherein saidpeptide comprises a cytotoxic agent joined thereto, such as aradiochemical, or a toxin.

Alternative 80 includes the method of Alternative 76, wherein saidpeptide comprises an antibody or antibody fragment.

Alternative 81 includes the peptide of anyone of Alternatives 1 to 35,further comprising a detectable label joined thereto, such as abiotinylated label, a radioactive label, a fluorescent label, or acolloidal gold label.

Alternative 82 includes the peptide of anyone of Alternatives 1 to 36,further comprising a cytotoxic agent joined thereto, such as aradiochemical, or a toxin.

Alternative 83 includes a method of inhibiting the proliferation ofhuman cancer cells comprising: identifying a human cancer patient;contacting immune cells of the human cancer patient with a peptide ofany of Alternatives 1 to 35; and detecting an inhibition ofproliferation of cancer cells of the patient or an induction of celldeath of cancer cells of the patient.

Alternative 84 includes the method of Alternative 83, wherein aninhibition of proliferation of cancer cells of the patient is detected.

Alternative 85 includes the method of Alternative 83, wherein at leastone of an induction of cell death of cancer cells or tumor regressivechanges is detected.

Alternative 86 includes the method of Alternative 83, wherein the cancercells are at least one colorectal cancer, renal cancer, breast cancer,skin cancer, ovarian cancer, prostate cancer, pancreatic cancer, lungcancer, malignant melanoma, small cell lung cancer, non-small lungcancer (adenocarcinoma), squamous cell carcinoma, bladder cancer,osteosarcoma, bronchial cancer, and hematopoietic cell cancer.

Alternative 87 includes the method of Alternative 83, further comprisingdetecting an increase in at least one of the proliferation, migration,endothelial transmigration, and cytotoxicity of immune cells of thehuman.

Alternative 88 includes the method of Alternative 83 wherein the immunecells are PBMCs.

Alternative 89 includes the method of Alternative 88, wherein the immunecells are lymphocytes.

Alternative 90 includes the method of Alternative 83, wherein saidpeptide is synthetic

Alternative 91 includes a method of removing a ligand bound to the LFA-1receptor of human lymphocytes comprising: contacting human lymphocyteswith a peptide of any of Alternatives 1-31; and detecting a reducedbinding of a ligand for the LFA-1 receptor.

Alternative 92 includes the =method of Alternative 91, wherein saidhuman lymphocytes are from a patient with cancer, a bacterial infectionor a viral infection.

Alternative 93 includes the method of Alternative 92, wherein saidpatient has at least one of colorectal cancer, renal cancer, breastcancer, skin cancer, ovarian cancer, prostate cancer, pancreatic cancer,lung cancer, malignant melanoma, small cell lung cancer, non-small lungcancer (adenocarcinoma), squamous cell carcinoma, bladder cancer,osteosarcoma, bronchial cancer, and hematopoietic cell cancer.

Alternative 94 includes a method of removing a ligand bound to the IL-2receptor of human lymphocytes comprising: contacting human lymphocyteswith a peptide of any of Alternatives 1 to 35; and detecting a reducedbinding of a ligand for the IL-2 receptor.

Alternative 95 includes the method of Alternative 94, wherein said humanlymphocytes are from a patient with cancer, a bacterial infection or aviral infection.

Alternative 96 includes the method of Alternative 95, wherein saidpatient has at least one of colorectal cancer, renal cancer, breastcancer, skin cancer, ovarian cancer, prostate cancer, pancreatic cancer,lung cancer, malignant melanoma, small cell lung cancer, non-small lungcancer (adenocarcinoma), squamous cell carcinoma, bladder cancer,osteosarcoma, bronchial cancer, and hematopoietic cell cancer.

Alternative 97 includes a method of reducing immunosuppression in ahuman that is immunosuppressed comprising: providing to a human, apeptide of any of Alternatives 1 to 35; and detecting a reduction ofimmunosuppression in said human or detecting activation or stimulationof an immune cell, as evidenced by an increase in CD69 or CD71expression, induction of the secretion of a signal substance, asevidenced by interferon gamma or IL-12 production, or stimulation of therelease of a cytolytic substance, as evidenced by the release ofgranzyme B or perforin. Optionally, the method includes detecting one ormore of enhanced cytotoxicity, cytokine production, cell migration,and/or cell proliferation.

Alternative 98 includes the method of Alternative 97, wherein said humanhas cancer, a bacterial infection or a viral infection.

Alternative 99 includes the method of Alternative 98, wherein saidcancer is colorectal cancer, renal cancer, breast cancer, skin cancer,ovarian cancer, prostate cancer, pancreatic cancer, lung cancer,malignant melanoma, small cell lung cancer, non-small lung cancer(adenocarcinoma), squamous cell carcinoma, bladder cancer, osteosarcoma,bronchial cancer, or hematopoietic cell cancer.

Alternative 100 includes the method of Alternative 99, wherein providingsaid peptide comprises administering to said human a compositionconsisting of at least 0.1% of the peptide by weight, for example, atleast 0.1%, 0.2%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20%, or30% of the peptide by weight, including ranges between any two of thelisted values

Alternative 101 includes a method of inhibiting the binding of a humanalbumin or a human albumin fragment to the LFA-1 receptor or the IL-2receptor or both on human lymphocytes comprising: providing a human thepolynucleotide or vector of anyone of Alternatives 36-41; and detectingan inhibition of binding of a human albumin or a human albumin fragmentto the LFA-1 receptor or the IL-2 receptor or both.

Alternative 102 includes a method of inhibiting the proliferation ofhuman cancer cells comprising: providing the polynucleotide or vector ofanyone of Alternatives 36-41 to a human that has cancer cells; anddetecting an inhibition of proliferation of said cancer cells.

Alternative 103 includes a method of removing a ligand bound to theLFA-1 receptor or IL-2 receptor or both of human lymphocytes comprising:contacting human lymphocytes with the polynucleotide or vector of anyoneof Alternatives 36 to 41; and detecting a reduced binding of a ligandfor the LFA-1 receptor or the IL-2 receptor or both.

Alternative 104 includes a method of reducing immunosuppression in ahuman that is immunosuppressed comprising: providing the polynucleotideor vector of anyone of Alternatives 36 to 41 to said human; anddetecting a reduction of immunosuppression or detecting activation orstimulation of an immune cell, as evidenced by an increase in CD69 orCD71 expression, induction of the secretion of a signal substance, asevidenced by interferon gamma or IL-12 production, or stimulation of therelease of a cytolytic substance, as evidenced by the release ofgranzyme B or perforin in said human. Optionally the method includesdetecting one or more of enhanced cytotoxicity, cytokine production,cell migration, and/or cell proliferation.

Alternative 105 includes a modified peptide of Alternatives 1 to 35,wherein said peptide comprises at least one modification, for example atleast one of a D amino acid, an N-terminal acetyl group, a C-terminalamide group, a glycosylated amino acid, a nitrosylated amino acid, acarbonylated amino acid, an oxidized amino acid, or wherein said peptideis joined to polyethylene glycol, a fatty acid, or a pharmacokineticmodifier.

Alternative 106 includes the modified peptide of Alternative 103,wherein said peptide is less than or equal to 30, 29, 28, 27, 26, 25,24, 23, 22, 21, 20, 19, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, or 6 aminoacids in length.

Alternative 107 includes a pharmaceutical composition comprising: thepeptide of any of Alternatives 1 to 35 or Alternatives 103 to 104; and apharmaceutically acceptable carrier, excipient, or diluent.

Alternative 108 includes the pharmaceutical composition of Alternative107, wherein the peptide comprises at least one of SEQ ID NOs: 1-33, 34,46-53, 62, 64-66, 68, 76, 94-96, 98, and 586.

Alternative 109 includes a method for identifying a patient in need oftreatment with an inhibitor of immunoregulatory peptides or structures,the method comprising: contacting immune cells of the patient in vitrowith a peptide of any of Alternatives 1-35; detecting a restoration ofreactivity of said immune cells; and classifying the patient as likelyto respond to treatment with the inhibitor of immunoregulatory peptidesor structures if said peptide inhibits proliferation of said immunecells.

Alternative 110 includes the method of Alternative 109, furthercomprising reducing immunosuppression in the patient in need, whereinreducing immunosuppression comprises providing to the patient in need, apeptide of any of Alternatives 1 to 35.

Alternative 111 includes the method of Alternative 110, furthercomprising detecting a reduction of immunosuppression in said human.

Alternative 112 includes the method of Alternative 109, furthercomprising reducing immunosuppression in the patient in need, whereinreducing immunosuppression comprises providing to the patient in need, avector or polynucleotide of any of Alternatives 36-41.

Alternative 113 includes the method of Alternative 112, furthercomprising detecting a reduction of immunosuppression or detectingactivation or stimulation of an immune cell, as evidenced by an increasein CD69 or CD71 expression, induction of the secretion of a signalsubstance, as evidenced by interferon gamma or IL-12 production, orstimulation of the release of a cytolytic substance, as evidenced by therelease of granzyme B or perforin in said human. Optionally, the methodincludes detecting one or more of enhanced cytotoxicity, cytokineproduction, cell migration, and/or cell proliferation.

Alternative 114 includes the isolated peptide of any of Alternatives 1to 23, wherein said peptide comprises an amino acid residue homologousto amino acid residue K2 of SEQ ID NO: 2.

Alternative 115 includes the isolated peptide of any of Alternatives 1to 23, wherein said peptide comprises an amino acid residue homologousto amino acid residue K9 of SEQ ID NO: 2.

Alternative 116 includes the isolated peptide of any of Alternatives 1to 23, wherein said peptide comprises an amino acid residue homologousto amino acid residue E15 of SEQ ID NO: 2.

Alternative 117 includes the isolated peptide of Alternative 114,wherein said peptide comprises an amino acid residue homologous to aminoacid residue K9 of SEQ ID NO: 2.

Alternative 118 includes the isolated peptide of Alternative 114,wherein said peptide comprises an amino acid residue homologous to aminoacid residue E15 of SEQ ID NO: 2.

Alternative includes the isolated peptide of Alternative 115, whereinsaid peptide comprises an amino acid residue homologous to amino acidresidue E15 of SEQ ID NO: 2.

Alternative 120 includes the isolated peptide of Alternative 114,wherein said peptide comprises an amino acid residue homologous to aminoacid residue K9 of SEQ ID NO: 2, and wherein said peptide comprises anamino acid residue homologous to amino acid residue E15 of SEQ ID NO: 2.

Alternative 121 includes the isolated peptide of any of Alternatives 1to 23 or Alternatives 114 to 120, wherein said peptide comprises atleast one non-naturally occurring amino acid.

Alternative 122 includes the isolated peptide of any of Alternatives 114to 120, wherein said peptide comprises at least one modification, forexample at least one of a D amino acid, an N-terminal acetyl group, aC-terminal amide group, a glycosylated amino acid, a nitrosylated aminoacid, a carbonylated amino acid, an oxidized amino acid, or wherein saidpeptide is joined to polyethylene glycol, a fatty acid, or apharmacokinetic modifier.

Alternative 123 includes the isolated peptide of anyone of Alternatives114 to 120, wherein said peptide is less than or equal to 30, 29, 28,27, 26, 25, 24, 23, 22, 21, 20, 19, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7,or 6 amino acids in length or a length defined by a range that isbetween any two of these numbers.

Alternative 124 includes the isolated peptide of anyone of Alternatives114 to 120, wherein said peptide is between 6 amino acids and 20 aminoacids in length, preferably between 8-16 amino acids in length, and mostpreferably between 9 and 15 amino acids in length.

Alternative 125 includes the isolated peptide of anyone of Alternatives114 to 120, wherein said peptide is joined to a support.

Alternative 126 includes the isolated peptide of anyone of Alternatives114 to 120, wherein said peptide is multimerized.

Alternative 127 includes an isolated polynucleotide comprising asequence encoding the peptide of any one of Alternatives 114-120.

Alternative 128 includes a vector comprising the isolated polynucleotideof Alternative 127.

Alternative 129 includes a vector comprising the isolated polynucleotideof Alternative 128.

Alternative 130 includes the isolated polynucleotide of Alternative 127or the vector of Alternative 128, wherein said peptide is less than orequal to 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 16, 15, 14, 13,12, 11, 10, 9, 8, 7, or 6 amino acids in length or a length defined by arange that is between any two of these numbers.

Alternative 131 includes the isolated polynucleotide of Alternative 127or the vector of Alternative 128, wherein said peptide is between 6amino acids and 20 amino acids in length, preferably between 8-16 aminoacids in length, and most preferably between 9 and 15 amino acids inlength.

Alternative 132 includes a protein complex comprising albumin or afragment of albumin bound to the peptide of anyone of Alternatives 114to 127.

Alternative 133 includes the protein complex of Alternative 132, whereinsaid protein complex is bound to a support.

Alternative 134 includes an isolated peptide comprising: X₁ X₂X₃-X₈ X₉X₁₀-X₁₄ X₁₅ X₁₆, wherein X₁ and X₁₆ is any amino acid or absent; X₂ isselected from the group consisting of M, N, P, G, E, R, K X₉ is selectedfrom the group consisting of T, R, K; X₁₅ is selected from the groupconsisting of P, D, E, Y, N, Q; and X₃-X₈ and X₁₀-X₁₄ is any amino acid.

Alternative 135 includes the isolated peptide according to Alternative134, wherein X₂ is selected from the group consisting of K, N, P and X₁₅is selected from the group consisting of P, D, E.

Alternative 136 includes the isolated peptide according to Alternative135, wherein X₂ and X₉ are K and X₁₅ is E.

Alternative 137 includes the isolated peptide according to Alternative136, wherein X₅-X₈ are F, F, V, K and X₁₀-X₁₁ are L, S.

Alternative 138 includes the isolated peptide according to Alternative137, wherein said peptide is KLDTFFVKLSLFTE (SEQ ID NO: 58).

Alternative 139 includes a pharmaceutical composition comprising theisolated peptide according to any of Alternatives 134 to 138 and apharmaceutically acceptable carrier, diluent or excipient.

Alternative 140 includes an antibody, monoclonal antibody or functionalfragment thereof comprising the isolated peptide according to any ofAlternatives 134 to 138.

Alternative 141 includes the antibody, monoclonal antibody or functionalfragment thereof according to Alternative 140, is a single domainantibody (SdAb).

Alternative 142 includes a kit comprising the isolated peptide accordingto any of Alternatives 134 to 138 and/or the antibody, monoclonalantibody or a functional fragment thereof according to any ofAlternatives 140 to 141 and instructions how to use said kit.

Alternative 143 includes an in vitro method comprising the steps of; (a)providing immune cells; (b) contacting said immune cells with theisolated peptide according to any of Alternatives 134 to 138 or theantibody, monoclonal antibody or functional fragment thereof accordingto any of Alternatives 140 to 141; and (c) determining a modulatingeffect of said immune cells such as by detecting activation orstimulation of an immune cell, as evidenced by an increase in CD69 orCD71 expression, induction of the secretion of a signal substance, asevidenced by interferon gamma or IL-12 production, or stimulation of therelease of a cytolytic substance, as evidenced by the release ofgranzyme B or perforin. Optionally, the method includes detecting one ormore of enhanced cytotoxicity, cytokine production, cell migration,and/or cell proliferation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates immunohistochemical staining of a malignant melanomametastases using affinity purified rabbit antibodies directed to theP3028 epitope.

FIG. 2 illustrates Western blot performed on tumor extracts usingantibodies directed against the 3028-structure.

FIG. 3 illustrates Sandwich ELISA detecting albumin exposing the P3028epitope in serum; competition with the P3028 peptide.

FIG. 4 illustrates IL-2 induced proliferation by PBMCs from healthycontrol samples and human immune cells (PBMC) from renal cell carcinomapatients (RCC) cultured in 10% autologous sera.

FIG. 5 illustrates a Kaplan Meyer analysis of renal cell carcinomapatients according to proliferative response to IL-2.

FIG. 6 illustrates analysis of the effect of four different peptides onIL-2 induced proliferation of PBMCs from healthy control samples.

FIG. 7 illustrates inhibition of the proliferative response to IL-2 byP3028 in the human ex vivo model using cancer patient PBMCs.

FIG. 8 illustrates effect of P3028 on TCR stimulated lymphocyteproliferation of PBMCs from four healthy persons.

FIGS. 9A-9B illustrates effect of albumin peptides on NK-cellcytotoxicity. FIG. 9A depicts effects for K5 and K6. FIG. 9B depictseffects for K12 and K13.

FIGS. 10A-B illustrates effect of P3028 on the spreading on peripheralblood leukocytes.

FIG. 11 illustrates effect of P3028 on migration of PBMCs studied usingthe Boyden chamber technique.

FIG. 12 illustrates effect of the C-(3218) and N-terminal (3325) partsof P3028 on IL-2 induced proliferation in comparison with the effect ofthe full length P3028.

FIG. 13 illustrates the inhibitory effect of P3028 on IL-2 inducedproliferation is not neutralized by the C-(3218) and N-terminal (3325)parts of P3028 alone or in combination.

FIGS. 14A-B illustrate inhibition of the binding of anti-LFA-1 antibodydirected to CD11a by incubation of normal PBMCs with patient sera.

FIGS. 15A-B illustrate inhibition of the binding of an anti-LFA-1, mAb,to mononuclear blood cells by P3028.

FIG. 16 illustrates staining of LFA-1 on PBMCs from a healthy controlsample (A), and a cancer patient before (B) and after (C) treatment withan antibody directed against the inhibitory P3028.

FIG. 17 illustrates staining of mononuclear blood cells by an anti-LFA-1antibody (A) is blocked by P3028 (B) or cancer patient serum (C).

FIGS. 18A and 18B illustrates ELISA analysis showing that the binding ofbiotinylated IL-2 to rhuIL-2R. FIG. 18B is a contrast-enhanced image ofFIG. 18A, so as to depict the binding data for non biotinylated IL-2(triangles).

FIG. 19 illustrates the α-chain of the IL-2 receptor (CD25) bindingP3028 (A) at the IL-2 binding site (B).

FIG. 20 illustrates antisera from rabbits immunized with P3028 binds toP3028.

FIG. 21 illustrates inhibition of the binding of rabbit-anti 3028 serumL to wells coated with the P3028 in an ELISA by albumin peptides.

FIGS. 22A and 22B illustrate effects of affinity purified antibodiesdirected against P3028 on the proliferative response to IL-2 of PBMCsfrom immunosuppressed cancer patients and normal control samples.

FIGS. 23A-B illustrate identification of P3028 inhibitors in solution.Based on previous analyses potential binders of P3028 were synthesizedon a chip. FIG. 23A illustrates results for assays 1-14. FIG. 23Billustrates results for assays 15-28. FIGS. 23A and 23B represent theleft and right sides, respectively, of a single graph that was enlargedto show the text more clearly. The Y axis has been reproduced in FIG.23B for reference.

FIG. 24A-D illustrate stimulatory activity of P28R on suppressedproliferative response to IL-2. FIGS. 24A, 24B, 24C, and 24Drespectively illustrate stimulatory activity for four different cancerpatients.

FIG. 25 illustrates binding of biotinylated P28R to a fresh frozenbreast cancer tumor.

FIG. 26 illustrates breast cancer tissue incubated with buffer (FIG.26A) or P28R (FIG. 26B) stained by an antibody directed against LFA-1.

FIG. 27 illustrates rampo scores for binding of P3028 to peptides havingsingle amino acid substitutions of each position of P28R.

FIG. 28 illustrates single amino acid substitutions of peptide P28Rhaving rampo scores greater than 500.

FIG. 29 illustrates rampo scores for binding of P3028 to P28R andN-terminal and/or C-terminal truncations of peptide P28R.

FIGS. 30A-B illustrate rampo scores for binding of P3028 to internaldeletion mutants, and single amino acid substitution mutants of peptideP28R. FIGS. 30A and 30B represent the left and right sides,respectively, of a single graph that was enlarged to show the text moreclearly. For reference, the Y axis has been reproduced in FIG. 30B.

FIG. 31 illustrates favorable electrostatic interactions and hydrophobicinteractions between peptide 3028 and peptide KKL15.

FIG. 32 illustrates alignments of cyclic peptides identified as bindingto P3028 in positional scan experiments (SEQ ID NOs: 265-267) and linearpeptides identified as binding to P3028 (SEQ ID NOs: 2, and 268-293).

FIGS. 33A and 33B illustrate effects of various concentrations ofpeptide P28R on MTS bioreduction in (FIG. 33A) PBMC's from healthycontrol samples, and (FIG. 33B) PBMC's from cancer patients.

FIG. 34 illustrates effect of P28R (aka “SCF 28R”) (N=9) and P27 (aka“SCF 27”) (N=8) on PBMCs from cancer patients, MTS measurements, day 7.

FIG. 35 illustrates response to IL-2 in cancer patients cells, measuredby BrdU incorporation.

FIGS. 36A-B illustrates effect of P28R (aka “P28”) on IL-2 inducedproliferation in cells of (FIG. 36A) high responders, and (FIG. 36B) lowresponders.

FIG. 37 illustrates effect of P28R (aka “SCF 28R”) and P27 (aka “SCF27”) on IL-2 stimulation of PBMCs from cancer patients, based on BrdUincorporation.

FIGS. 38A-D illustrate effect of P28R (aka “SCF 28R”) and P27 (aka “SCF27”) on IL-2-induced proliferation based on BrdU incorporation (FIGS.38A, 38C) and MTS incorporation (FIGS. 38B, 38D). Shown are cells of twodifferent patients, (FIGS. 38A, 38B) and (FIGS. 38C, 38D) respectively.

FIG. 39 illustrates enzyme linked immunosorbent spot assays of cellswith (bottom row) and without (top row) P3028 peptide.

FIG. 40 illustrates data from enzyme linked immunosorbent spot assays ofcells with and without P3028 peptide.

FIGS. 41A-B are a series of graphs illustrating effects of modifiedpeptides on activation of PBMCs from healthy control person. PBMCs wereincubated with the peptides (40 μg/mL) for 24 hours in RPMI plus 10%human AB serum. Activation is determined as percentage of cells withenhanced marker CD69 using flow cytometry. FIG. 41A illustrates resultsof two experiments (410 and 412) performed for each peptide. FIG. 41Billustrates results of two experiments (414 and 416) performed for eachpeptide.

FIGS. 42A-B are a series of graphs illustrating effects of the fulllength peptide P28R and the 6 amino acid central sequence (32230,FFVKLS, SEQ ID NO: 62) in culture medium containing normal human ABserum. Activation is determined as percentage of cells with enhancedmarker CD69 or CD71 using flow cytometry. PBMCs were incubated with thepeptides (40 μg/mL) for 24 hours in RPMI plus 10% human AB serum. FIG.42A illustrates the results of two experiments (420 and 422) performedfor each peptide. FIG. 42B illustrates the results of two experiments(424 and 426) performed for each peptide.

FIG. 43 is a graph illustrating a comparison of the full length peptideP28R and the 6 amino acid central sequence (32230, FFVKLS, SEQ ID NO:62) in culture medium containing sera from two different cancer patients(“human ca serum 1” 430 and (“human ca serum 2” 432).

FIGS. 44A-B are a series of microscope images illustrating P28Rtreatment of human prostate cancer, PC3, in a xenograft model in nudemice. Tumor was injected intra-tumorally with P28R (FIG. 44A) and onlythe drug solvent (FIG. 44B). Staining for Caspase 3 440 (demonstratinginduction of apoptosis) and an absence of staining 442 are depicted.

FIGS. 45A-B are a series of microscope images illustrating intra-tumoraltreatment of B16 melanoma with P28R. The inflammatory infiltrate wasdemonstrated after 3 days of treatment using a polyclonal rabbitantibody directed against CD45 (FIG. 45A), and control sections wereincubated with rabbit IgG at the same concentration (FIG. 45B). Staining450 and an absence of staining 452 are depicted.

FIGS. 46A-B are a series of graphs illustrating Effect of modifiedpeptides on activation of PBMCs from healthy control person. Activationis determined as percentage of cells with enhanced marker CD69 (FIG.46A, showing results of two experiments, exp 1 460 and exp 2 462) orCD71 (FIG. 46B, showing results of two experiments, exp 1 464 and exp 2466) using flow cytometry. PBMCs were incubated with the peptides (40μg/mL) for 48 hours in RPMI plus 10% human AB serum.

FIG. 47A-B are a series of microscope images illustrating occurrence ofthe immunoinhibitory 3028 structure in two areas (FIG. 47A and FIG. 47B,respectively) of a human breast cancer. Immunohistochemical staining(470) using biotinylated P28R is depicted. An absence of staining 472 isobserved in FIG. 47A.

DETAILED DESCRIPTION OF THE INVENTION

Several immunoregulatory peptide inhibitors, which interact withimmunoregulatory peptides that cause immunosuppression in a human (e.g.,a human having cancer, enduring or chronic infectious or inflammatorydisease), have been developed. Preferred immunoregulatory peptideinhibitors bind to proteins or peptides that comprise the P3028structure and/or the P3028 sequence (SEQ ID NO: 185). With reference tosome embodiments and description herein, the P3028 structure refers topolypeptides, such as peptides, proteins, and the like that include theP3028 sequence (SEQ ID NO: 185). The P3028 structure can includemacromolecules such as peptides, proteins, and the like that arerecognized by antibodies that bind specifically to P3028 structures (seeExample 1 and FIG. 2). For example, aggregates of albumin, denaturedalbumin and other damaged albumins can include the P3028 structure. Insome contexts in the present application, the P3028 structure, P3028sequence, and P3028 are terms used interchangeably. Molecules having theP3028 structure interact with receptors on immune cells, such as theIL-2 receptor and the LFA-1 receptor, causing immunosuppression. Assuch, it is contemplated herein that peptides, proteins, albuminfragments, damaged albumin (e.g. denature albumin) and albuminaggregates can include the P3028 structure, and can interact with immunecell receptors such as the IL-2 receptor and LFA-1 receptor.Immunosuppression can be characterized by a reduced immune cellproliferation, spreading and migration, as well as, NK-cellcytotoxicity. In the presence of an immunoregulatory peptide inhibitor,as described herein; however, the immunosuppression mediated by theP3028 structure can be altered (e.g., reduced, ameliorated, eliminated,or removed altogether). In some experiments, for example, it was foundthat an immunoregulatory peptide inhibitor can remove a moleculeincluding a P3028 structure from the LFA-1 receptor thereby altering theimmunosuppression mediated by P3028 structure. Accordingly, thedescription that follows provides details on many different classes ofimmunoregulatory peptide inhibitors including, but not limited to,antibody or antibody fragment based immunoregulatory peptide inhibitors,peptide based immunoregulatory peptide inhibitors, peptidomimeticimmunoregulatory peptide inhibitors, modified immunoregulatory peptideinhibitors (e.g., containing a D amino acid, N-terminal acetyl, or Cterminal amide group), cyclic peptides inhibitors, and aptamer basedimmunoregulatory peptide inhibitors. Methods of using compositions (asdescribed herein) to reduce immunosuppression or an aspect thereof(e.g., reducing a P3028-mediated inhibition of immune cellproliferation, spreading, migration, or NK-cell cytotoxicity), as wellas, approaches to inhibit, reduce, or alter the progression of cancer orinflammatory disease are provided. The composition can comprise, consistof, or consist essentially of an immunoregulatory peptide inhibitor asdescribed herein. Accordingly, immunoregulatory peptide inhibitors asdescribed herein can be useful for ameliorating, reducing the symptomsof, reducing the severity of, and/or treating immunosuppression.

Immunoregulatory peptide inhibitors as described herein interact with orbind to proteins or peptides that comprise at least one of sequence SEQID NOs: 183-185 or 188-246. Such peptides can have immunoregulatoryproperties similar to P3028 sequences and structures (see Examples 17 to26).

With reference to some embodiments in the following disclosure, aminoacids, or amino acid residues can be referred to by either athree-letter or a one-letter code. Twenty amino acids are typicallyencoded by the genetic code, and can be referred to using the followingcodes or abbreviations herein: Arginine (“Arg” or “R”), Histidine (“His”or “H”), Lysine (“Lys” or “K”), Aspartic Acid (“Asp” or “D”), GlutamicAcid (“Glu” or “E”), Serine (“Ser” or “S”), Threonine (“Thr” or “T”),Asparagine (“Asp” or “N”), Glutamine (“Gln” or “Q”), Cysteine (“Cys” or“C”), Glycine (“Gly” or “G”), Proline (“Pro” or “P”), Alanine (“Ala” or“A”), Valine (“Val” or “V”), Isoleucine (“Ile” or “I”), Leucine (“Leu”or “L”), Methionine (“Met” or “M”), Phenylalanine (“Phe” or “F”),Tyrosine (“Tyr” or “Y”), Tryptophan (“Trp” or “W”).

With reference to some embodiments in the following disclosure by“peptide” is meant a protein and/or a fragment of a protein, which mayhave several different lengths (e.g., at least or equal to 2, 3, 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49, 50, 60, 70, 80, 90, 100, 120, 140, 160, 180,200, 240, 260, 300, 350, 400, 450, 500, 600, 700, 800, or 1000 aminoacids or a range defined by any number in between these numbers).

With reference to some embodiments in the following disclosure, aminoacids (and their residues) can be categorized according to variouscharacteristics of the side chains of the alpha carbon of the aminoacid. It is noted that the twenty naturally occurring amino acidsencoded by the genetic code, and also synthetic amino acids arecontemplated herein. As used herein “hydrophobic amino acid” (includingpluralaizations and variations of this root term) refer to naturallyoccurring or synthetic amino acids having a hydrophobic side chain, forexample A, V, I, L, M, F, Y, or W. As used herein, “positively chargedamino acid” (including pluralaizations and variations of this root term)refer to naturally occurring or synthetic amino acids having apositively charged side chain, for example, R, H, or K. As used herein,“negatively charged amino acid” (including pluralaizations andvariations of this root term) refer to naturally occurring or syntheticamino acids having a negatively charged side chain, for example, D or E.As used herein, “hydrophobic non-aromatic carbon chain amino acid”(including pluralaizations and variations of this root term) refer tonaturally occurring or synthetic amino acids having a hydrophobicnon-aromatic carbon side chain, for example, A, V, I, or L. As usedherein, “polar uncharged amino acid” (including pluralaizations andvariations of this root term) refer to naturally occurring or syntheticamino acids having a polar uncharged side chain, for example, S, T, N,or Q.

With reference to some embodiments and description herein, the bases ofnucleic acids, such as DNA, RNA, and the like can be referred to byeither the name of the base or a one letter code. One skilled in the artwill appreciate that the genetic code is degenerate, in that for someamino acid residues, two or more three-base codons can encode the sameamino acid. Thus, some one letter codes, and described herein, canrepresent one of two or more bases, for example to describe two or morepossible nucleic acids that can encode a single amino acid. One-lettercodes used herein include: “A” (adenine), “G” (guanine), “C” (cytosine),“T” (thymine), “R” (one of adenine or guanine), “Y” (one of cytosine orthymine), “M” (one of adenine or cytosine), “K” (one of guanine orthymine), “S” (one of cytosine or guanine), “W” (one of adenine orthymine), “H” (one of adenine, cytosine, or thymine), “B” (one ofcytosine, guanine, or thymine), “V” (one of adenine, cytosine, orguanine), “D” (one of adenine, guanine, or thymine), and “N” (one ofadenine, guanine, cytosine, or thymine).

The terms “de-blocking” and “unblocking” as used herein (includingpluralization and variations of this root term) refers to displacing abound immunoregulatory peptide or P3028 structure from a receptor. Assuch, de-blocking or unblocking a receptor shifts the equilibriumbetween receptor-bound and non-receptor-bound immunoregulatory peptidetowards the “non-receptor-bound” category. For example, an LFA-1receptor or IL-2 receptor can be de-blocked in accordance withembodiments herein by displacing a bound peptide P3028 from the LFA-1receptor of IL-2 receptor. For example, an LFA-1 receptor or IL-2receptor can be de-blocked in accordance with embodiments herein bydisplacing any immunoregulatory peptide comprising one or more sequencesfor Tables 1-4 from the LFA-1 receptor or IL-2 receptor.

The term “immune cell activation” as used herein, and pluralizations andvariations of this root term (including such as “activating an immunecell”), refers to immune cell proliferation, activating or enhancingexpression of CD69 and/or CD71, induction of secretion of a signalsubstance (e.g. IFNγ or IL-12), induction of secretion of a cytolyticmolecule (e.g. perforin or granzyme B), enhanced cytotoxicity, cytokineproduction, cell migration, cell proliferation, or two or more of theselisted items. By way of example, immune cell activation in accordancewith some embodiments herein can occur if an immune cell proliferates,or if an immune cell begins to express detectable CD69, or if an immunecell increases its expression of CD71, or if an immune cell secretesIFNγ, IL-12, or IFNγ and IL-12.

Available data support a major role of the immune system in cancercontrol sample. Malignant tumors, however, can exploit a large number ofimmunoregulatory mechanisms to suppress immune mediated anti-tumorreactivity. Based on the observation that an increased serumconcentration of interleukin-6 (IL-6) often is correlated to a poorprognosis in cancer patients of various diagnoses, the origin andinduction of this cytokine was explored. It was found that proteolyticfragmentation or denaturation of normal serum albumin generatedneo-structures, which exhibit immunoregulatory activity by binding toimmune cells. Accordingly, a new class of immunoregulatory substanceswas discovered.

The existence of albumin sequences having neo-structures that bind toimmune cells was identified using a human ex vivo model based onaffinity chromatography over an “Artificial Cell Surface Column” (ACS).The effect of different albumin fragments on IL-2 induced proliferationof human immune cells (PBMCs) was analyzed in the ACS system (seeExample 9). Briefly, PBMCs were cultured for seven days in the presenceof IL-2 and the various synthetically prepared albumin fragments.Proliferation was measured as incorporation of ³H thymidine during thefinal 18 hours. One of the peptides, P3028 (also referred to as “peptide3028” and having the amino acid sequence VFDEFKPLVEEPQNLIK—SEQ ID NO:185) regularly inhibited IL-2 induced proliferation, but none of theother peptides identified by their binding to the artificial cellsurface showed as much inhibitory activity as the P3028sequence/structure (see FIG. 6). Accordingly, the immune cellproliferative response induced by LFA-1 or IL-2 could be inhibited byP3028, indicating that P3028 sequence/structure may be acting through atleast the LFA-1 or IL-2 receptor.

The enhanced incorporation of ³HTdR can be the result of an enhancedspecific activity of the intracellular thymidine pools and thereby anenhanced specific activity of DNA, thus, not necessarily mirroring anincrease in the number of cells. It was therefore considered of be ofimportance to explore a different mode of stimulation of lymphocyteproliferation and to measure the response using a different method, theMTS technique (see Example 3). Accordingly, T-cells were stimulated incultures on plates pre-coated with a monoclonal antibody directedagainst CD3 and the number of metabolically active cells was determinedusing MTS staining after 3 to 7 days of culture (see FIG. 8). As shown,P3028 sequence/structure had an inhibitory effect. It can be argued thatthe reduced MTS staining caused by P3028 sequence/structure might be dueto a reduced cell metabolism; however, taken together the results fromboth models of lymphocyte proliferation, a reduced metabolism shouldreasonably reduce the endogenous thymidine pools and thereby result inan increased uptake of exogenous thymidine/specific activity of thethymidine pools, which then should be erroneously registered as anenhanced proliferation. The ³H-TdR was actually reduced in theseexperiments, indicating inhibition of proliferation. Accordingly, it wasconfirmed that peptides comprising the 3028 sequence effectivelyinhibited IL-2 mediated immune cell proliferation.

Peptide fragments encompassing the C- and N-terminal parts of P3028 werethen synthesized and the ability of these peptides (separately and incombination) to inhibit IL-2 induced proliferation of immune cells wasanalyzed (see Example 6). An N-terminal fragment of P3028 (i.e., P3325having the amino acid sequence VFDEFKPLVE (SEQ ID NO: 186)) and aC-terminal fragment of P3028 (i.e., P3218 having the amino acid sequenceEPQNLIK) (SEQ ID NO: 187)) were synthesized. It was determined that theinhibitory activity of these two fragments of P3028 alone or incombination was weaker than P3028 (see FIG. 12) and the peptidefragments of 3028 do not inhibit the effect of P3028 on IL-2 inducedproliferation (see FIG. 13).

It was then determined that peptides comprising the P3028sequence/structure sequence not only interacted with the IL-2 receptorbut also interacted with the LFA-1 receptor. In a first set ofexperiments, it was found that the P3028 peptide has the capacity tomodulate the binding of an LFA-1 specific monoclonal antibody to theLFA-1 receptor on human immune cells (see Example 7). This LFA-1specific monoclonal antibody is a potent inhibitor of IL-2 inducedimmune cell proliferation (see Vyth-Dreese et al., Eur. J. Immunol.12:3292-3299 (1993)). A standard immunohistochemical staining procedurewas employed in the presence and absence of the P3028 peptide. Briefly,immune cells (PBMCs) from healthy individuals and cancer patients werecompared. The cells were fixed utilizing acetone, blocked with 10% humanAB-serum with or without P3028, and incubated with a monoclonalanti-LFA-1 antibody and a secondary antibody followed by colordevelopment using Fast Red. As shown in FIG. 16A, a clear membranestaining 3 was found on PBMCs from healthy control samples in contrastto PBMCs from a patient with advanced cancer, which exhibited weakstaining 5. However, when the PBMCs from this cancer patient wereincubated with an antibody specific for the 3028 structure for 24 hoursthe membrane staining 3 appeared, indicating that the antibody bound the3028-structure and thereby unblocked LFA-1 (see FIG. 16C) and thediscussion infra.

Since P3028 sequence/structure significantly inhibited the proliferativeresponse of immune cells to IL-2, the effect of P3028 sequence/structureon the binding of IL-2 to CD25 was studied. The fusion protein of CD25and the Fc-part of IgG was bound to protein G coated micro-plates/ELISAplates and the plates were incubated with biotinylated IL-2 with orwithout the presence of P3028. Surprisingly, the binding of IL-2 to CD25was enhanced by the presence of P3028, providing evidence of athree-part interaction between IL-2, CD25 and P3028 (see FIGS. 18A-B).Even if the binding of IL-2 to CD25 is enhanced, the proper assembly ofthe high affinity receptor and/or signal transduction is blocked as theP3028 sequence/structure is a potent inhibitor of IL-2 inducedproliferation. Using computer-assisted molecular modeling, it wasdetermined that the P3028 sequence/structure binds to CD25 at the IL-2binding site (see FIG. 19). These results provide greater evidence thatthe P3028 sequence/structure has at least a dual immunoregulatorycapacity since it binds to both the LFA-1 receptor and the IL-2receptor.

The ability of specific albumin fragments to impact NK-cell cytotoxicitywas also evaluated. In these experiments, synthetic peptidescorresponding to albumin fragments (P3028, P3026, and P3027) (SEQ IDNOs: 185, 183, and 184, respectively) were prepared and the amount oflysis of K562 target cells was assessed (see Example 4). Inhibition wasnot seen in the presence of the control sample peptide P3027 but P3028and to a lesser degree P3026 caused a reduction in NK-cell cytotoxicity(see FIGS. 9A-B). Accordingly, peptides having the sequence of P3028effectively inhibit NK-cell cytotoxicity.

The ability of specific albumin fragments to inhibit leukocyte spreadingand immune cell migration was also analyzed. Briefly, buffy coat cellswere prepared from heparinized blood by Dextran assisted sedimentation.These cells were then washed twice in PBS and transferred to cleanslides. The cells strongly adhered to the glass surface and spread out;however, pre-treatment of these cells with P3028 at a concentration of10 μg/ml for 15 minutes efficiently inhibited the immune cell spreading(see Example 5). Similarly, the impact of P3028 on PBMC migration wasstudied using the Boyden chamber technique (see Example 5). As shown inFIG. 11, P3028 is a potent inhibitor of immune cell migration (p<0.002).

Antibodies specific for proteins having the P3028 sequence/structurewere prepared, purified, and characterized (see Example 9). Polyclonalantibodies specific for P3028 were generated in rabbits or goats.Briefly, rabbits were immunized with P3028 and specific antibodies wereaffinity purified using P3028. These antibodies were found to bind toP3325 (the N-terminal fragment SEQ ID NO: 186) but not P3218 (theC-terminal fragment (SEQ ID NO: 187) of P3028.

In a next series of experiments, the expression of P3028 in malignanttumors (e.g., malignant melanoma, renal cell carcinoma, and colorectalcancer) was identified by immunohistochemical staining using affinitypurified rabbit anti-3028 antibodies (see Example 9). Theimmunohistochemical staining of malignant melanoma, renal cellcarcinoma, and colorectal cancer tissue slices showed that the P3028sequence containing molecules are widely expressed and/or localized oncancer cells. These results were further supported by the demonstrationof 3028-structures in tumor extracts prepared from malignant melanomametastases using a Western technique (see Example 1). Appreciable 3028structures (approximately, slightly larger than 66 kD) were identifiedby the Western blot but the 3028 sequence was also detected in full sizealbumin and larger molecules (see FIG. 2). These results provideevidence that molecules comprising the 3028 structure are generated notonly by proteolytic fragmentation but also by denaturation. Accordingly,it was determined that P3028 sequence and/or molecules that comprisethis sequence are present in and/or localized to tumor tissue.

An ELISA technique was then used to confirm that proteins and peptidescomprising the 3028 sequence were present in human serum. Briefly, asandwich assay was employed, wherein affinity purified anti-3028antibodies were coated onto high protein binding ELISA microwells(capture antibody), and a 1% solution of heat-inactivated serum, spikedwith increasing concentrations of P3028, was then added to the wells.After washing, a biotinylated mouse anti-human albumin monoclonalantibody was added and the amount of bound antibody was detected withHRP-conjugated streptavidin and TMB chromogen substrate (see Example 1).The serum concentration was found to be in the range of 1.2-1.6 μg/mlP3028 equivalents in one serum pool from 5 healthy control samples, 1healthy control sample serum and 2 sera obtained from cancer patients.The amount of 3028 containing molecules was determined as the amount ofP3028, which inhibits 50% of the binding of 3028 structures in the serumto the capture antibody (directed against the 3028 epitope) in thesandwich ELISA (see FIG. 3). The amount of these 3028-substances inserum may be considerably more as the molecular weight of albumin isabout 35 times more than that of P3028, but their epitope specificreactivity is accurately determined using the method described above.

Experiments were then performed using a first class of inhibitors thatare specific for the P3028 sequence/structure. The proliferativeresponse of human immune cells from healthy individuals and cancerpatients after IL-2 induction were analyzed in the presence and absenceof antibodies specific for the P3028 sequence/structure (see Example 9).That is, the proliferative response of PBMCs from a patient having renalcell carcinoma and a patient having malignant melanoma were compared tothe proliferative response of PBMCs obtained from a healthy individualin the presence and absence of antibodies specific for the P3028sequence/structure. It was determined that in the presence of theantibodies that are specific for the P3028 sequence/structure, enhancedproliferation of the PBMCs after IL-2 induction was seen. That is, theantibody inhibitor for the P3028 sequence/structure was able to removethe blockade on IL-2-induce proliferation of the immune cells mediatedby the P3028 sequence/structure. These results demonstrate that abinding partner for the P3028 sequence/structure (e.g., an antibody orbinding fragment thereof specific for P3028), can reduce the immunesuppression mediated by the P3028 sequence/structure.

The P3028 sequence/structure is a potent physiological inhibitor of theimmune system, and is a possible a target for therapeutic compositionsthat can modulate immune activity. Antibodies directed against the P3028sequence/structure reversed cancer-related immunosuppression, which wasmodeled as reduced proliferative response of PBMCs to IL-2 in a human exvivo model (see Example 9). Moreover, the outcome in this modelcorrelated to over-all survival of the cancer patients (see Example 2).Therefore, it was contemplated that additional binding partners for theP3028 sequence/structure (e.g., peptides, cyclic peptides,peptidomimetics, antibodies and portions thereof) may be useful forinhibiting the P3028 sequence/structure-mediated immune suppression.

Three peptide-based binding partners for the P3028 sequence/structurewere initially developed and the binding capacity of these inhibitorswith P3028 in solution was tested, as shown in FIG. 23 (see Example 10).Only one molecule, SCF28, had a solubility sufficient to allow testingin biological human ex vivo models. Based on this structure, a firstdrug candidate, P28R (SEQ ID NO: 2), was developed.

Since P28R strongly bound to P3028, the ability of P28R to inhibit thefunction of the P3028 sequence/structure was tested. As described above,the β2-integrins plays a major role in the normal function of the immunesystem. However, the binding of the P3028 sequence/structure, to theβ2-integrin LFA-1 has a substantial immunosuppressive effect. Asdemonstrated above (see Example 7), in assays staining for LFA-1, themembrane staining of PBMCs from cancer patients is markedly decreasedcompared to normal control samples. The exposure of LFA-1 could,however, be enhanced by incubating PBMCs from cancer patients with anantibody directed against the inhibitory P3028 sequence/structure (seeExample 7 and FIG. 16C). Similarly incubation of fresh frozen tumoursections with peptide P28R (SEQ ID NO: 2) de-blocks LFA-1 of tumourinfiltrating lymphocytes (i.e. displaces a bound immunoregulatorypeptides or P3028 strucutres from the LFA-1 receptors), resulting in anenhanced binding of the anti-CD11a antibody (FIG. 26). These resultsshowed that the LFA-1 receptor was unblocked by removal of the P3028structure by the antibody. To test the ability of P28R to inhibit theP3028 structure, fresh frozen tumor sections without fixation wereincubated for 4-20 hours in the presence of the drug candidate, P28Rbefore staining for LFA-1 (see Example 15). For comparison, tumorsections were incubated with phosphate buffered saline only. As shown inFIG. 26, P28R effectively unblocked the LFA-1 receptor (e.g. displacedbound immunoregulatory peptides or 3028 structures from the LFA-1receptor) and thereby markedly enhanced the functional expression ofLFA-1 enabling migration and cytotoxic activity of these cells.Accordingly, P28R decreases the binding of P3028 to LFA-1 andeffectively inhibits the immune suppression mediated by P3028. It iscontemplated that incubation with P28 core (SEQ ID NO: 62) in accordancewith some embodiments herein also de-blocks LFA-1 (e.g. displaces boundimmunoregulatory peptides or 3028 structures from the LFA-1 receptor).

As such, the receptors of P3028 include LFA-1 and the alpha chain of theIL-2 receptor (CD25). Binding of a monoclonal antibody to CD11a (thealpha chain of LFA-1) was used to study the possible occurrence of aphysiological blocker of LFA-1 and the de-blocking activity of P28R andantibodies directed to P3028. Accordingly, it is further contemplatedthat, similar to the LFA-1 receptor, the IL-2 receptor can be de-blockedby immunoregulatory peptide inhibitors as described herein (e.g. boundimmunoregulatory peptides or 3028 structures can be displaced from theIL-2 receptor). As such, in some embodiments, an immunoregulatorypeptide inhibitor as described herein deblocks an IL-2 receptor, forexample an IL-2 receptor that has been blocked by any one or more of thepeptides listed in Tables 1-4 (e.g. a peptide comprising SEQ ID NO:185).

Incubation of PBMCs from healthy controls with P3028 (FIGS. 15 and 17)or cancer patient sera (FIG. 17) blocks the binding of the anti-CD11aantibody to LFA-1. Furthermore, incubation of PBMCs from advanced cancerpatients with an antibody directed against P3028 restitutes the bindingof the anti-CD11a antibody to LFA-1 (FIG. 16). P3028 can bind to PBMCs(see FIG. 15A depicting no peptide added, and FIG. 15B, depictingpreincubation with peptide 3028; anti-LFA-1 mAb HI111 was inhibited bypreincubation with peptide 3028, indicating binding to mononuclear bloodcells by peptide 3028).

Since P28R unblocks LFA-1 receptors that are suppressed by the P3028sequence/structure (e.g. displaces bound immunoregulatory peptides or3028 structures from the LFA-1 receptor), the ability of P28R to enhanceimmune stimulation was tested in human ex vivo models. The stimulatoryactivity of P28R on PBMCs was measured using the MTS or CFSE techniquesin 7 healthy control samples and 7 cancer patients of various diagnoses(see Example 13). Even in the absence of other types of stimulation,P28R has a significant stimulatory activity in 6 out of 7 cancerpatients; whereas PBMCs from control samples showed only weak or nostimulation (see Example 13). Similar to the studies on the efficacy ofantibodies directed against P3028 to reverse cancer relatedimmunosuppression above (see Example 9; see FIG. 22), the ability of theP28R inhibitor to unblock the IL-2 receptor and thereby induce immunecell proliferation was investigated. Cultures of PBMCs from fourdifferent treatment naïve patients were each treated with P28R, andproliferation of PBMCs was measured. While PBMC's that had highproliferative activity before P28R treatment were largely unaffected bythe drug (see FIG. 24C and FIG. 24D), PBMCs with a low initialproliferation were markedly stimulated (see FIG. 24A and FIG. 23B; seeExample 13). Thus, the P28R inhibitor effectively induces immune cellproliferation when the immune cells are bound and suppressed by theP3028 sequence/structure, even in the absence of additional stimulation.

Since cancer cells have been shown to be enriched for P3028 structures(see Example 1 and FIGS. 1-2), the ability of P28R to specifically bindcancer cells was investigated. The binding of biotinylated P28R totumors was studied. Three breast cancers, two renal cell carcinomas andfour malignant melanomas were analyzed. Notably, all of the differenttypes of tumors analyzed in the experiments bound P28R. The stainedbreast cancer section, shown in FIG. 25, for example, exhibits a strongpositive signal, indicating the presence of the inhibitoryP3028-structure in this tumor, and ability of P28R to bind to this tumor(see Example 14).

Since the P3028-structure inhibits lymphocyte migration, as well as,cytotoxic activity (see Examples 4 and 5), an immune system mediatedattack against positively-staining tumor areas is expected to beefficiently suppressed so long as the a P3028-containing structure ispresent and not sequestered by a binding partner for the P3028sequence/structure (e.g., an antibody, binding fragment thereof, and/oran inhibitory peptide, such as P28R, or a peptidomimetic correspondingto the P28R structure). Consistent with the observation that P3028strongly binds the LFA-1 receptor, lymphocytes were not stained by thisprocedure since the P3028 structure was blocked by binding to LFA-1 onthese cells.

Based on the ability of P28R to bind the P3028 sequence/structure,unblock the LFA-1 receptor, and ameliorate the P3028sequence/structure-dependent immunosuppression, P28R was used as atemplate compound to identify additional compounds that bind to andsequester P3028. Variants of the P28R structure were synthesized, andtested for the ability to bind P3028 using PEPSCAN technology (seeExample 12). A library of peptides that include each genetically-codedamino acid substitution at each amino acid position of P28R (i.e., 19substitutions for each position) was synthesized. Each peptide wasaffixed to a support pin, and the peptide library was incubated withP3028. The binding of the candidate inhibitors to P3028 was detected bya sandwich ELISA, where a rabbit anti-mouse peroxidase (rampo) secondaryantibody was employed (see Example 12). The binding of each peptide wasthen assigned a rampo score (see FIG. 27). Peptide P28R had rampo valuesranging between about 262 and 460 with a mean value of 370. In someembodiments, the immunoregulatory peptide inhibitor as disclosed herein,is selected for a desired P3028 binding rampo score. In someembodiments, the desired P3028 binding rampo score is greater than orequal to the rampo score of P28R. It is also contemplated that somepeptides that bind to P3028 with less affinity than P28R havetherapeutic application. Some peptides with binding affinities that areless than P28R, for example, may modulate signal transduction eventsdifferently than P28R by virtue of the fact that the affinity to P3028is less. Accordingly, embodiments also include any peptide that binds toP3028, wherein said peptides have a rampo score that is less than thatexhibited by P28R. Accordingly, contemplated embodiments includepeptides that bind with any affinity to P3028 (e.g., any one or more ofthe peptides provided in Table 5.1, preferably peptides that modulatethe immune system (e.g., modulate, upregulate or down regulate a markerof the immune system or immunosuppression, such as reducing aP3028-mediated inhibition of immune cell proliferation, spreading,migration, or NK-cell cytotoxicity).

A total of 31 substitutions of peptide P28R (SEQ ID NOs: 3-33) had rampovalues greater than 500 (see FIG. 28), indicating that these 31 peptides(strong binding partners for P3028) can be used to efficiently bind andsequester P3028 and thereby reduce P3028-mediated immunosuppression.Table 6.1 lists these 31 peptides that were evaluated in assays andshown to have appreciable binding to P3028. Additionally, the bindingstrength of substituted peptides at each position (based on rampo score)was compared to the binding strength of a P28R (SEQ ID NO: 2) controlsample for the same position (see Example 12). Peptides that bound witha rampo score substantially equal to or greater than that of the P28Rcontrol sample (i.e., at peptides that bound to P3028 with at least 98%of the rampo score of the P28R control sample) were identified (SEQ IDNOs: 268-393). Table 6.2 lists these 126 peptides that were shown tohave appreciable binding to P3028. It is noted that these 126 peptidesinclude the 31 peptides of Table 6.1. Accordingly, 126 different bindingpartners for P3028 were identified by this initial screen and thesemolecules or variants thereof (e.g., variants having D amino acids,N-terminal amides, and/or C terminal acetyl groups or peptidomimetics oraptamers corresponding to these binding partners) can be used to inhibitthe binding of the P3028 sequence/structure to an immune cell andthereby alleviate, or reduce P3028-dependent immunosuppression. Onevariant of P28R, Peptide KKL15 (SEQ ID NO: 1), which lacks only aC-terminal arginine, is thought to bind to the P3028 sequence/structurethrough both charged and hydrophobic interactions. As shown in FIG. 31,positively charged amino acids of KKL15 interact with negatively chargedamino acids on P3028 and hydrophobic amino acids generate hydrophobiccontacts enhancing the interaction.

To further map the P3028 binding domain of P28R, deletions, andtruncations of P28R were synthesized, and tested for binding to P3028using the PEPSCAN assay. This approach led to the development of manymore binding partners for P3028. While deletion of residues 6-9(“FFVK”—SEQ ID NO: 182) and the C-terminal amino acids tended to reducethe binding of peptides to P3028 based on rampo score (see Example 12and FIG. 30), several deletions and truncations of peptide P28R have arampo score comparable to, or higher than peptide P28R (see, e.g., SEQID NOs: 34, 64-66, 68, and 76). Additionally, peptides deleted up to atleast 8 amino acids from the N-terminus of P28R (see, e.g., SEQ ID NOs:46-53) retained a high affinity to P3028, as measured by rampo score,providing evidence that inhibitors that are smaller than P28R can beuseful for binding to and sequestering P3028, preventing the interactionof P3028 with immune cell receptors, such as the IL-2 or LFA-1receptors, thereby reducing P3028-induced immunosuppression.

Because P28R was shown to have a modulatory effect on IL-2 stimulationof immune cell proliferation (see Example 2), it was furtherinvestigated whether P28R would have a modulatory effect on otheraspects of IL-2 stimulation of immune cells. PBMC's from eight healthycontrol samples and nine cancer patients with various diagnoses werecultured in a modified version of the ex vivo model of Example 2 forseven days in the presence of various doses of P28R (either “no P28R”control samples, or 5 μg/mL, 10 μg/ml, or 20 μg/ml of P28R). A dosedependent stimulation of the mitochondrial metabolism measured asconversion of MTS was observed in 5/8 (see FIG. 33A) control samples and9/9 cancer patients (see FIG. 33B). Similar results were obtained whenthe PBMCs were cultured for only three days (see Example 28).

To identify the effectiveness of other inhibitors of immunomodulatorypeptides, the effect of P28R (SEQ ID NO: 2) on mitochondrial metabolismbased on MTS conversion was compared to the effect of a closely relatedpeptide P27. P27 has the sequence KKLDTFFKKLSLFTER (SEQ ID NO: 264), andis a variant of P28R that differs in that V8 of P28R is substituted toK8 in P27. P28R binds to P3028 more efficiently than P27 (P27 bindsP3028 with a rampo score of 253, while a P28R control sample binds P3028with a rampo score of 308; see Example 12). The concentrations wereeither untreated control samples, 5 μg/mL (“SCF28-R5” and “SCF275”), 10μg/ml (“SCF28-R10” and “SCF2710”), 20 μg/ml (“SCF28-R20” and “SCF2720”),or 40 μg/ml (“SCF28-R40” and “SCF2740”). The results are shown in FIG.34. While P28R stimulated the cells of cancer patients in adose-dependent manner, P27 had no effect (see Example 29).

The effect of P28R (SEQ ID NO: 2) on IL-2 induced proliferation was alsomeasured in a BrdU incorporation assay. PBMCs from six healthy controlsamples and ten cancer were harvested in a modified version of the exvivo model. Four out of six control samples had a high proliferativeresponse to IL-2 compared to four out of ten cancer patient samples (seeFIG. 35). These differences in proliferative response to IL-2 in PBMCsdemonstrated the difference existence of high and low responders to IL-2stimulation (see Example 30).

The response of high responders and low responders to various doses ofP28R was compared. Cells from either high responders or low responderswere cultured with various doses of P28R (see FIGS. 36A and 36B).IL-2-induced proliferation was measured as BrdU incorporation. WhileP28R had no stimulatory effect in cells from patients with a highresponse to IL-2 (N=4) (see FIG. 36A), P28R had a stimulatory effect oncells from patients with a low response to IL-2 (N=6) (see FIG. 36B).Accordingly effects of P28R on binding to and blocking immunoinhibitoryactivity of P3028 were demonstrated in in the ex vivo model, as additionof P28R to the cultures had no effect on proliferation when added toPBMCs from healthy controls and cancer patients with a normalproliferative rate, but the proliferation of PBMCs from immunosuppressedcancer patients were significantly stimulated by P28R. Without beinglimited by any theory, in some embodiments P28R (SEQ ID NO: 2) or P28core (SEQ ID NO: 62) binds to a blocker of immune cell proliferation,and induces immune cell proliferation.

The effect of P27 (SEQ ID NO: 264) was then compared to the effect ofP28R (SEQ ID NO: 2) on IL-2 induced proliferation as measured by BrdUIncorporation. PBMCs from low responder cancer patients were withvarious concentrations of either P28R of P27, ranging from no peptide(“untreated cells”), to 5 μg/mL, 10 μg/ml, or 20 μg/ml. As shown in FIG.37, both P28R and P27 enhanced the proliferative rate of PBMC's inducedby IL-2 as measured by BrdU incorporation. When comparing the resultsshown in FIG. 37 to those of FIG. 34, P27 was observed to enhance IL-2stimulation of cell proliferation as measured by BrdU incorporation, butnot mitochondrial metabolism as measured by MTS conversion. On the otherhand, P28R was observed to enhance both MTS conversion and BrdUincorporation in response to IL-2 stimulation (see Example 31).

The different effects of different inhibitors of immunoregulatorypeptides on BrdU incorporation and MTS conversion were furtherinvestigated. The effects of P28R on IL-2 stimulation of immune cellproliferation differed significantly, depending on which assay was used(see FIG. 38). Peptide P28R had a stimulatory activity of MTS conversionin seven day cultures of PBMCs in 100% of cancer patients examined (N=9)and in 63% of healthy control samples examined (N=8). In contrast, P28Rstimulated incorporation of BrdU in seven day cultures of PBMCs fromonly 17% (N=6) and 20% of (N=10) patients. P28R stimulated IL-2 inducedproliferation, measured as incorporation of BrdU, in PBMC cultures fromcancer patients with a low proliferative response to IL-2. On the otherhand, PBMCs from 67% of healthy control samples examined (N=3) and 50%of cancer patients (N=4) were not stimulated by IL-2 when the effect wasmeasured as MTS conversion (see Example 32 and FIG. 38). However, PBMCsfrom all these persons (“non-responders”) who did not respond whenmeasured with MTS were significantly stimulated by IL-2 when the effectwas measured as incorporation of BrdU (see FIG. 38). In two patients,the response to IL-2, measured as BrdU incorporation, was enhanced byP28R (see FIGS. 38A and 38C), but this effect of P28R was only observedin one of these patients when MTS conversion was used (see FIG. 38B).Thus, while in one patient (see FIGS. 38A and 38B) the stimulatoryactivity of IL-2 was registered using both BrdU and MTS, in the otherpatient, the stimulatory activity of IL-2 was registered using BrDU only(see FIG. 38C) (see Example 32). Based on these observations, it wascontemplated that effects on the metabolic activity measured as MTSconversion does not always correlate with DNA synthesis measured asincorporation of BrdU, and different populations of patients can responddifferently to inhibitors of immunoregulatory peptides.

It was contemplated that other molecules that bind to P3028 could beidentified. These additional binding molecules could also potentiallyblock P3028. Looped 6-mere peptides were synthesized, and 6-meres thatdemonstrated appreciable binding to P3028 were identified (see Table 12,SEQ ID NOs: 265-267) (see Example 19). It was observed that two of the6-meres with the strongest binding to P3028 based on rampo scorepossessed homology to linear peptides that bind 3028 (see FIG. 32).

In addition to P3028, several other albumin fragments and syntheticpeptides were found to bind to the immune cells. Some of these fragmentscan have immunomodulatory activity similar to P3028, can bind to immunecells similar to P3028, and/or can bind to immunomodulatory antibodiesthat recognized P3028. In a first set of experiments, albumin fragmentswere generated by trypsin digestion and the tryptic fragments were foundto bind to immune cells in the ACS system described herein (see Example17). Table 1 provides a listing of trypsin-generated fragments ofalbumin, which bind to immune cells in the ACS system, as detected byMALDI-TOF analysis.

TABLE 1 Trypsin-generated albumin fragments that bind to ACS PercentAlbumin SEQ ID NO: Absorbed Sequence Positions 194 71% KYLYEIAR 161-168195 64% KVPQVSTPTLVEVSR 438-452 196 60% VFDEFKPLVEEPQNLIK 397-413 19759% VPQVSTPTLVEVSR 439-452 198 42% RPCFSALEVDETYVPK 509-524 199 41%FQNALLVR 427-434 200 36% SLHTLFGDK 89-97 201 36% LKECCEKPLLEK 299-310202 35% LCTVATLR  98-105 203 34% YLYEIAR 162-168 204 32% CCAAADPHECYAK384-396 205 29% AAFTECCQAADK 187-198 206 26% CCTESLVNR 500-508 207 25%QEPERNECFLQHK 118-130 208 23% AVMDDFAAFVEK 570-581 209 22% NECFLQHK123-130 210 20% ONCELFEQLGEYK 414-426 211 18% QEPERNECFLQHK 118-130 21213% VHTECCHGDLLECADDR 265-281 213 8% FKDLGEENFK 35-44 214 3%YICENQDSISSK 287-298 215 2% LDELRDEGK 206-214 216 1% DDNPNLPR 131-138

In a second set of experiments, denatured human serum albumin wasdegraded by asparaginase (ASN-N), and the ability of these proteolyticfragments to bind with immune cells was evaluated in the ACS system.Again, the immune cell binding peptides were identified by comparingadsorbed and unadsorbed peptide solutions using the MALDI TOF technique.These peptides are shown in Table 2.

TABLE 2 Asp-N-generated albumin fragments that bind to ACS SEQ IDPercent Albumin NO: Absorbed Sequence Positions 217 100%DHVKLVNEVTEFAKTCVA 62-79 218 100% DDKETCFAEEGKKLVAASQAALGL 586-609 21987% DRVTKCCTESLVNRRPCFSALEV 495-517 220 86% DETYVPKEFNAETFTHA 518-535221 65% DSISSKLKECCEKPLLEKSHCIAEVEN 293-319 222 65% DKLCTVATLRETYGEM 96-112 223 100% YSVVLLLRLAKTYETTLEKCCAAADPHEC 364-398 YAKVF 224 100%KLCTVATLRETYGEMADCCAKQEPERNEC  96-130 FLQHK 225 100%ICTLSEKERQIKKQTALVELVKHKPKAT 536-572 KEQLKAVM 226 100%LAKYICENQDSISSKLKECCEKPLLEKHC 283-319 IAEVEN 227 100%VFLGMFLYEYARRHPDYSVVLLLRLAKTY 348-388 ETT LEKCCAAA 228 100%LGEENFKALVLIAFAQYLQQCPFEDHVK 37-79 LVNEVTEFAKTCVA 229 100%RVTKCCTESLVNRRPCFSALEVDETYVP 495-535 KEFNAETFTFHA 230 37%YLSVVLNQLCVLHEKTPVSDRVTKCCCT 475-517 ESLVNRRPFSALEV

Additionally, several synthetic peptides were synthesized, as shown inTable 3, and the binding of these molecules to immune cells using theACS system was evaluated.

TABLE 3 Synthetic albumin peptides SEQ Peptide Albumin ID NO: NameSequence Positions 183 3026 NEETFLKKYLYEIARRHPYFYAP 153-176 184 3027ELFEQLGEYKFQNALLVR 417-434 188 3029 KVPQVSTPTLVEVSR 438-452 189 2604KLVNEVTEFAKT 65-76 190 2605 NEETFLKKYLYE 153-168 191 2606 LDELRDEGKAS205-217 192 2607 EMADCCAKQEPE 110-122 193 2608 ELFEQLGEYKF 417-427

Additionally, several albumin fragment peptides bind specifically to andHSA-specific antibody with immunomodulatory effects (mAb A) (seeExample 18). These peptides are shown in Table 4.

TABLE 4 Albumin peptides that bind to monoclonal antibody mAb ASEQ ID NO: Sequence Albumin Positions 231 LVNEVTEFAK 066-075 232SLHTLFGDK 089-097 233 LCTVATLR 098-105 234 ETYGEMADCCAK 106-117 235YLYEIAR 162-168 236 LDELRDEGK 206-214 237 YICENQDSISSK 287-298 238LKECCEKPLLEK 299-310 239 HPDYSVVLLLR 362-372 240 CCAAADPHECYAK 384-396241 QNCELFEQLGEYK 414-426 242 FQNALLVR 427-434 243 CCTESLVNR 500-508 244AVMDDFAAFVEK 570-581 245 LSQRFPK 243-249 246 DDNPNLPR 131-138

It is contemplated that inhibitors to any one or more of the peptideslisted in Tables 1-4 can be generated in much the same way thatinhibitors to P3028 were generated. In brief, polyclonal and monoclonalantibodies that are specific for any one or more of the peptides inTables 1-4 can be easily generated using conventional techniques inimmunology. Antibody binding fragments can also be prepared and isolatedusing conventional techniques in immunology. These antibodies orantibody fragments can be human, or humanized, as described herein.Using an approach similar to that described supra and in Examples 9 and10, these peptide inhibitors can be evaluated on a chip based assay andbiochemical assays, such as immune cell proliferation in the presenceand absence of the peptide inhibitors, can be evaluated. The sectionbelow provides more information on the development of immunoregulatorypeptide inhibitors, preferably inhibitors of P3028.

It is contemplated that inhibitors of any one or more of the peptideslisted in Tables 1-4 can comprise modifications of the P28R (SEQ ID NO:2) or P28 core (SEQ ID NO: 62) sequence, and further can be useful forreducing inhibition of the LFA-1 receptor, or for stimulating immunecells. To identify modification to inhibitor peptides in accordance withsome embodiments herein, positional scan data was used to study theinfluence of substitution of different types of amino acids in eachposition of P28R (SEQ ID NO: 2) on the binding of P3028 (SEQ ID NO:185). Each amino acid in the peptide sequence of P28R (SEQ ID NO: 2) wasexchanged with all of the naturally occurring amino acids, and bindingof P3028 (SEQ ID NO: 185) to each peptide on a solid phase chip wasassessed (see, e.g. Example 36). A number of optional modifications toP28R in accordance with embodiments herein are summarized in Tables 5.3,5.4, 5.5, 5.6, and 13. Optionally, an inhibitor peptide in accordancewith some embodiments herein can comprise one or more of themodifications of Table 5.3 or Table 13. Optionally, an inhibitor peptidecomprises a central core of positions 2, 5-11, and 15 as provided inTable 5.3, and the remaining position are omitted or substituted withsubstantially any amino acid. Optionally, an inhibitor peptide comprisesa central core of positions K2, T5-S11, and E15 of SEQ ID NO: 2, and theremaining position are omitted or substituted with substantially anyamino acid.

From the positional scan data it is also noted that a “core peptide” canbe identified, FFVKLS (SEQ ID NO: 62) (referred to herein as “P28core”). In some embodiments, a peptide comprising, consisting of, orconsisting essentially of P28 core (SEQ ID NO: 62) is provided. Thepeptide can comprise no more than about 30 amino acid residues, forexample no more than about 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20,19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, or 6 amino acidresidues. In some embodiments, the core peptide de-blocks an LFA-1receptor (e.g. displaces bound immunoregulatory peptides or 3028structures from the LFA-1 receptor) that has been bound by one or moreimmunoregulatory peptides of Tables 1-4.

Based on the positional scan data, it is contemplated that substitutionsof SEQ ID NO: 2 can be useful in accordance with some embodiments hereinfor binding P3028, de-blocking the LFA-1 receptor from P3028-mediatedinhibition (e.g. displacing bound P3028 peptide and P3028-structurecontaining molecules from the LFA-1 receptor), and/or stimulating immunecells. The activity of peptide P28R (SEQ ID NO: 2) and modifications ofP28R was studied in a human ex vivo model using PBMCs from a healthycontrol human in short term cultures, and with PBMC activation measuredas a percentage of cells with enhanced CD69 (see Example 37). It wasobserved that P28R (SEQ ID NO: 2) and peptide 31135 (KKLDTFFVYLSLFTER)(SEQ ID NO: 589) directly stimulate healthy PBMC's in this ex vivomodel, but peptides 30677 (KKLDTFFVKLSLMTER) (SEQ ID NO: 583), 30678(KKLDTFFVKLQLFTER) (SEQ ID NO: 584), 30680 (KKLDTVMVKLQLMTER) (SEQ IDNO: 585), 30864 (KSLDTFFVKLSLFTER) (SEQ ID NO: 587); 30685(KKLDTFFVKLSLFTFR) (SEQ ID NO: 588); and 31136 (KKLDTFFVNLSLFTER) (SEQID NO: 590), and 31138 (KKLDTFFVDLSLFTER) (SEQ ID NO: 591) did notstimulate the healthy PBMC's in this ex vivo model (see FIGS. 41A and41B). As such, in some embodiments, a composition comprising, consistingessentially of, or consisting of P28R (SEQ ID NO: 2), peptide 31135 (SEQID NO: 589), or a combination of P28R and peptide 31135 is provided todirectly stimulate immune cells. As such, in some embodiments, acomposition comprising, consisting essentially of a peptide of SEQ IDNO: 2, SEQ ID NO: 62, or any of SEQ ID NOs: 583-586 or 587-595, or acombination of these peptides is provided.

It is noted that peptide 31135 comprises a Y at the positioncorresponding to position 9 of SEQ ID NO: 2 and position 4 of SEQ ID NO:62. (see Tables 5.3 and 5.5). In some embodiments, a compositioncomprising, consisting essentially of, or consisting of a modifiedpeptide comprising a modification of P28R comprising a Y at position 9of SEQ ID NO: 2 is provided. Optionally, the immune cells can comprisehealthy immune cells. Optionally, the immune cells can comprise immunecells in cancer patient serum, for example cancer patient immune cells.In some embodiments, a composition comprising, consisting essentiallyof, or consisting of a modified peptide comprising a modification of P28core comprising a Y at position 4 of SEQ ID NO: 62 is provided.Optionally, the immune cells can comprise healthy immune cells.Optionally, the immune cells can comprise immune cells in cancer patientserum, for example cancer patient immune cells.

As P28R (SEQ ID NO: 2) can bind to P3028 and stimulate PBMC's fromhealthy controls in short term cultures, for example when in a culturemedium comprising RPMI plus 10% normal human AB serum (see Example 37),it is contemplated that truncations of P28R in accordance with someembodiments herein can be useful for binding to inhibitors of any one ormore of the peptides listed in Tables 1-4. Truncations of P28R wereassessed for their ability to activate PBMC's (see Example 38). PBMCswere incubated with the peptides (40 μg/mL) for 24 hours in RPMI plus10% human AB serum. PBMC activation was measured as percent cells withenhanced expression of either CD69 (FIG. 42A) or CD71 (FIG. 42B) usingflow cytometry. As shown in FIGS. 42A and 42B, peptide P28R (SEQ ID NO:2) effectively activated healthy PBMC's in this ex vivo model, butpeptide 32251 (SEQ ID NO: 592) and peptide 32230 (“P28 core”) (FFVKLS)(SEQ ID NO: 62) did not. However, PBMCs were also incubated with thepeptides in cancer sera from dogs, or in caner sera from human cancerpatients (see FIG. 43). It was observed that full length peptide P28R(SEQ ID NO: 2) and the P28 core peptide (peptide 32230) (SEQ ID NO: 62)activated PBMCs in the presence of cancer serum. As such, it iscontemplated that in accordance with some embodiments herein, P28R, P28core, or combinations of these peptides are useful for stimulatingimmune cells in the serum of a subject that has cancer.

In some embodiments, a peptide comprising, consisting of, or consistingessentially of P28 core (SEQ ID NO: 62) is provided. Optionally, thepeptide comprising, consisting of, or consisting essentially of P28 core(SEQ ID NO: 62) can bind to P3028 peptide. It was observed that P28 corepeptide (SEQ ID NO: 62) can bind the 3028 peptide as efficiently as thefull length peptide P28R, and can induce activation (e.g. proliferation,enhanced expression of CD69 and/or CD71, secretion of IL-12 of IFNγ, orsecretion of perforin or granzyme B, enhanced cytotoxicity, cellmigration, or cytokine production) of PBMC's in cancer serum (seeExample 38 and FIG. 43), but that in an ex vivo model comprising shortterm cultures of PBMC's, the P28 core peptide (SEQ ID NO: 62) notstimulate PBMC activation (CD69 and CD71) as the P28R peptide does (seeFIGS. 42A and 42B). Accordingly, in some embodiments, a peptidecomprising, consisting of, or consisting essentially of P28 core (SEQ IDNO: 62) binds to P3028 peptide as efficiently or substantially asefficiently as P28R (SEQ ID NO: 2). In some embodiments, P28R (SEQ IDNO: 2 is provided to bind to P3028 and de-block cellular receptors (e.g.displaces bound immunoregulatory peptides or 3028 structures from thecellular receptors). Optionally P28R can further have a directstimulatory activity on immune cells. In some embodiments, P28 core (SEQID NO: 62) is provided to bind to P3028 and de-block cellular receptors(e.g. displaces bound P3028 peptides or 3028 structures from thecellular receptors).

It has also been observed that, biotinylated P28R has been shown to binddirectly to PBMCs as demonstrated by immunocytochemistry or rosetting ofP28R coated beads (binding of beads to the cells). Accordingly, in someembodiments, P28R is provided to bind directly to PBMCs. In someembodiments, P28R comprising a detectable moiety is provided to bind toPBMCs. In some embodiments, P28R comprising a toxin is provided to bindto PBMCs. In some embodiments, peptide 31135 comprising a toxin or adetectable moiety is provided.

The effect of P28R (SEQ ID NO:2) on cancer cells was further studied inin vivo models in nude and immunocompetent mice. P28R was injectedintra-tumorally into human pancreas cancer in a xenograft model in nudemice, and induced tumor cell apoptosis after one day (see Example 39).P28R induced Caspase 3, a marker of ongoing apoptosis, while treatmentof tumors with the drug solvent only did not induce Caspase 3 (see FIGS.44A and 44B). In some embodiments, P28R (SEQ ID NO: 2) has a directcytotoxic action on tumor cells, for example, prostate cancer cells. Insome embodiments, a peptide of Table 5.3, or a modified P28R peptidecomprising at least one modification of Table 5.2 has a direct cytotoxicaction on tumor cells, for example prostate cancer cells.

As it was observed that P28R has an immunostimulatory effect (see, e.g.Example 37), the capacity of P28R (SEQ ID NO: 2) to activate the immunesystem was also evaluated. P28R, 40 microgram in 100 microliter wasinjected intra-tumorally into B16 melanoma in B16 melanoma-inoculatedimmunocompetent mice, C57B1 (see Example 40). Tumors were taken outafter 3 days, and sections were immunohistochemically stained using apolyclonal rabbit anti-CD45 antibody. The dominating cells in the tumorsafter P28R treatment were inflammatory cells, as indicated by CD45immunostaining 450 (see FIG. 45A). The staining was not observed 452 ina control tumor section incubated with rabbit IgG at the sameconcentration (FIG. 45B). It is contemplated that in some embodimentsP28R (SEQ ID NO: 2), P28 core (SEQ ID NO: 62), a peptide of SEQ ID NO:586 or 589, or a modified P28R peptide comprising at least onemodification of Table 5.2 can activate the immune system, for example todirect an immune response against tumor cells. In some embodiments, oneor more of the listed peptides is administered at or near a tumor. Insome embodiments, one or more of the listed peptides is administeredperi-tumorally. In some embodiments, one or more of the listed peptidesis administered systemically.

As it is contemplated that modifications of P28R can be useful forimmune cell stimulation, the influence of various amino acidsubstitutions and additions to P28R on the immunostimulatory effect wasfurther studied. Effects of modified peptides on the activation of PBMCsfrom a healthy control person were assessed (see Example 41). PBMCs wereincubated with the peptides (40 μg/mL) for 48 hours in RPMI plus 10%human AB serum, and PBMC activation was determined by flow cytometrybased on the percentage of cells with enhanced marker CD69 or CD71.Peptides P28R (SEQ ID NO: 2), P28 core (peptide 32230) (SEQ ID NO: 62),32251 (KKLDTFFPKLSLFTER) (SEQ ID NO: 592), 32814 (RKLDTFFVKLSLFTERRR)(SEQ ID NO: 586), 32815 (KKLDQFFVKLSQHNER) (SEQ ID NO: 595), 32665(KKLDTFMVKLSQHTER) (SEQ ID NO: 593), and 32819(KKLDTFFVKLSLFTER(C(PEG24))) (SEQ ID NO: 594) were tested. As shown inFIG. 46, peptide 32814 (SEQ ID NO: 586), had a stimulatory effect inshort term cultures similar to that of P28R (SEQ ID NO: 2) (batchCS8040) for both CD69 enhancement (see FIG. 46A) and CD71 enhancement(see FIG. 46B).

In addition to therapeutic applications, diagnostic applications of P28Rand truncations and modifications thereof were also contemplated. Forexample, information about patients systemic and local (intra-tumoural)immune status can be obtained using reagents comprising P28R, or atruncation or modification thereof.

It is contemplated that the occurrence of immunoinhibitory3028-structures in tumors can be identified by immunohistochemicalstaining using either an antibody directed against P3028 or usinglabeled P28R (SEQ ID NO: 2) or P28 core (SEQ ID NO: 62), for examplebiotinylated P28R or P28 core. FIG. 47 shows two areas of a human breastcancer stained using biotinylated P28R. Staining 470 is observed in FIG.47B. Staining is not observed in FIG. 47A. An absence of staining isindicated 472.

As such, areas of tumors comprising P3028 structures (as well as areasnot comprising these structures) can be identified using labeledpeptides in accordance with embodiments herein. In some embodiments, apeptide of SEQ ID NO: 2, SEQ ID NO: 62, SEQ ID NO: 584, a peptide listedin Table 5.4, or a modified P28R or P28 core peptide comprising one ormore modifications listed in Table 5.3 or Table 13 is provided, andfurther comprises a detectable moiety. The peptide comprising thedetectable moiety can bind to one or more immunoregulatory peptides ofTables 1-4, for example P3028 (SEQ ID NO: 185).

Ameliorating Immunosuppression

As the inhibitors of immunoregulatory peptides described herein can beuseful for removing immunosuppression, some embodiments herein comprisemethods of ameliorating, reducing the symptoms of, reducing, or treatingimmunosuppression. In some embodiments a subject suffering fromimmunosuppression is identified. The subject can comprise a human, or anon-human mammal. A composition comprising at least one of theinhibitors of immunoregulatory peptides described herein can beadministered to the patient. The composition can comprise at least onepeptide comprising, consisting of, or consisting essentially of any oneof SEQ ID NOs: 1-33, 34, 46-53, 62, 64-66, 68, 76, 94-96, 98, 265-393,583-586, 587-595, or a modified P28R or P28 core peptide comprising oneor more of the modifications of Table 5.3 or Table 13. The peptide canhave length is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids or a length defined by a range between any two of thesenumbers. Optionally, the composition can further comprise a buffer asdescribed herein, for example, Trizma, Bicine, Tricine, MOPS, MOPSO,MOBS, Tris, Hepes, HEPBS, MES, phosphate, carbonate, acetate, citrate,glycolate, lactate, borate, ACES, ADA, tartrate, AMP, AMPD, AMPSO, BES,CABS, cacodylate, CHES, DIPSO, EPPS, ethanolamine, glycine, HEPPSO,imidazole, imidazolelactic acid, PIPES, SSC, SSPE, POPSO, TAPS, TABS,TAPSO or TES. Optionally, the composition can further comprise adegradable particle as described herein. The composition can beadministered to the subject via a variety of routes, for example,systemically, at the site of immunosuppression (e.g. if there is localimmunosuppression by a tumor), or near the site of immunosuppression,for example within 10 cm 9 cm, 8 cm, 7 cm, 6 cm, 5 cm, 4 cm, 3 cm, 2 cm,1 cm, or 0.5 cm of the site of immunosuppression. Optionally a secondtherapeutic agent can be administered in addition to the composition,for example prior to, concurrently with, or subsequent to theadministration of the composition. For example, the second therapeuticagent can comprise an immunostimulatory agent. Optionally, activation ofimmune cells (e.g. enhanced expression of CD69 and/or CD71, secretion ofIL-12 of IFNγ, or secretion of perforin or granzyme B, enhancedcytotoxicity, cytokine production, cell migration, and/or cellproliferation) of the subject can be detected. For example, activationof immune cells can be detected as enhanced expression of one or moremarkers of immune cells, for example CD69, CD71, and the like.Activation of immune cells (e.g. enhanced expression of CD69 and/orCD71, secretion of IL-12 of IFNγ, or secretion of perforin or granzymeB, enhanced cytotoxicity, cytokine production, cell migration, and/orcell proliferation) can be detected by a number of techniques known tothe skilled artisan, for example flow cytometry, immunohistochemistry,ELISA, western blotting, immunoblotting, quantitative PCR, detection ofBUdR incorporation to measure proliferation, and the like. Without beinglimited by any theory, different types of immunosuppressor cells,regulatory T-cells, immature dendritic cells (iDC), tumor associatedmacrophages (TAM) and myeloid derived suppressor cells (MDSC), canfunction immunosuppression, and further, other immunosuppressormechanisms, such as serum blocking factors, circulating immunecomplexes, enhanced IL-1Ra production and enhanced intra-tumoralproteolytic activity can function in cancer related immunosuppression.As such, in some embodiments, treatment, amelioration, reduction, orreduction of the symptoms of immunosuppression can be determined by achange in activity, phenotype, or proliferation of an immunosuppressivecell, or a change in expression level or localization of animmunosuppressive factor.

Inhibitors of Immunoregulatory Peptides

Some embodiments include inhibitors of immunoregulatory peptides such asP3028 and/or one or more of the immunoregulatory peptides listed inTables 1-4 (SEQ ID NOs: 183-184, and 188-246), also referred to asblockers of albumin derived immunoregulatory peptides, binding partnersfor immunoregulatory peptides, or immunoregulatory peptide inhibitors.The immunoregulatory peptide inhibitors can include, but are not limitedto: peptides, cyclic peptides, peptidomimetics, proteins, nucleic acids,antibodies; antibody fragments, nucleic acid aptamers; peptide aptamers;and small molecules. The following section provides more details onantibody or antibody fragment-based immunoregulatory peptide inhibitors.

Antibody or Antibody Fragment-Based Immunoregulatory Peptide Inhibitors

Some embodiments include antibody or antibody fragment basedimmunoregulatory peptide inhibitors. Methods that use theseimmunoregulatory peptide inhibitors to inhibit immunosuppression in asubject (e.g., a subject having cancer or a pathogenic infection such asa bacterial or viral infection) are also contemplated. The core antibodystructural unit is known to comprise a tetramer. Each tetramer iscomposed of two identical pairs of polypeptide chains, each pair havingone “light” chain (about 25 kDa) and one “heavy” chain (about 50-70kDa). The amino-terminal portion of each chain includes a variableregion of about 100 to 110 or more amino acids primarily responsible forantigen recognition. The carboxy-terminal portion of each chain definesa constant region primarily responsible for effector function. Heavychains are classified as mu, delta, gamma, alpha, or epsilon, and definethe antibody's isotype as IgM, IgD, IgG, IgA, and IgE, respectively. Anadditional isotope, IgY is found in avian hosts. The chains all exhibitthe same general structure of relatively conserved framework regions(FR) joined by three hyper variable regions, also called complementaritydetermining regions or CDRs. The CDRs from the two chains of each pairare aligned by the framework regions, enabling binding to a specificepitope. From N-terminal to C-terminal, both light and heavy chainscomprise the domains FR1, CDR1, FR2, CDR2, FR3, CDR3 and FR4. Theassignment of amino acids to each domain is in accordance with thedefinitions of Kabat, Sequences of Proteins of Immunological Interest(National Institutes of Health, Bethesda, Md. (1987 and 1991)), orChothia & Lesk J. Mol. Biol. 196:901-917 (1987); Chothia et al., Nature342:878-883 (1989).

Accordingly, some embodiments include a composition that comprises,consists of, or consists essentially of an immunoregulatory peptideinhibitor that comprises an antibody or antibody fragment comprising adomain, which binds to one or more regions of an immunoregulatorypeptide, such as P3028 or one or more of the immunoregulatory peptidesprovided in Tables 1-4 (SEQ ID NOs: 183-184 and 188-246). In someembodiments, the antibody or antibody fragment is from a mouse, rabbit,rat, hamster, guinea pig, goat, donkey, bovine, horse, camel, cow,chicken, or human host. In some embodiments, the antibody or fragment isof isotype IgG, IgM, IgA, IgD, IgE, or IgY. In some embodiments, theantibody or fragment is part of a collection of polyclonal antibodies.In some embodiments, the antibody is monoclonal. In some embodiments,the antibody or fragment is chimeric. In some embodiments, the antibodyor fragment includes at least one region form a human host, which can beat least one of the following Fc; Fab; light chain variable region;light chain CDR1, CDR2, or CDR3; heavy chain variable region; heavychain CDR1, CDR2, or CDR3; light chain framework region; light chainFR1, FR2, FR3, or FR4; heavy chain framework region; heavy chain FR1,FR2, FR3, or FR4. In some embodiments, the antibody includes at leastone CDR or FR of a non-human host. In some embodiments, the antibodyregions are in accordance with the definition of Kabat. In someembodiments, the antibody regions are in accordance with the definitionof Chothia. In some embodiments, the antibody regions are in accordancewith a combination of the definition of Kabat and Chothia. In someembodiments, the antibody or antibody fragment mimics one or more of thepeptides described in Table 5.1, Table 5.4, Table 5.5, or Table 5.6.

Antibodies can be readily produced using conventional techniques inimmunology, for example techniques described in (U.S. Pat. Nos.8,142,784 and 7,628,986). Antibodies generated in non-human hosts can behumanized, for example by substituting at least one variable region ofthe antibody of the non-human host into a human antibody. Moreover,human antibodies can be generated, for example in a transgenic hostanimal. Transgenic animals (e.g., mouse, such as XENOMOUSE) can beengineered, upon immunization, to produce a full repertoire of humanantibodies in the absence of endogenous immunoglobulin production(Jakobovits et al. (1993) Proc. Natl. Acad. Sci. USA, 90:2551;Jakobovits et al. (1993) Nature 362:255-258; Bruggermann et al. (1993)Year in Immuno. 7:33; and U.S. Pat. Nos. 5,591,669; 5,589,369;5,545,807). Moreover, phage display technology (McCafferty et al. (1990)Nature 348:552-553) can be used to produce human antibodies and antibodyfragments in vitro, from immunoglobulin variable (V) domain generepertoires from unimmunized donors (Johnson, Kevin S. and Chiswell,David J. (1993) Current Opinion in Structural Biology 3:564-571). Arepertoire of V genes from unimmunized human donors can be constructedand antibodies to a diverse array of antigens (including self-antigens)can be isolated essentially (Marks et al. (1991) J. Mol. Biol.222:581-597; Griffith et al. (1993) EMBO J. 12:725-734; U.S. Pat. No.5,565,332; U.S. Pat. No. 5,573,905). Many phage display libraries areknown, or can be generated, for example those of (U.S. Pat. No.7,985,840). Human antibodies may also be generated by in vitro activatedB cells (U.S. Pat. Nos. 5,567,610; 5,229,275). Thus, some embodimentsinclude generating antibodies that bind to P3028 (SEQ ID NO: 185) and/orthe peptides of Tables 1-4 (SEQ ID NOs: 183-184 and 188-246). In someembodiments, the antibodies are humanized antibodies that include atleast one variable region of a non-human host antibody. In someembodiments, the antibodies are human antibodies generated in anon-human host, for example a transgenic animal. In some embodiments,the transgenic animal is a transgenic mouse. In some embodiments, theantibodies are generated in vitro. In some embodiments, the antibodiesare generated using phage display technology. In some embodiments, theantibodies are generated in activated B cells in vitro.

Antibodies and antibody fragments can be configured to deliver cytotoxiccompounds to a target site. Thus, some embodiments include antibodiesand/or antibody fragments bound to cytotoxic compounds as describedherein. In some embodiments, the antibodies or antibody fragments arebound to the cytotoxic compounds via a cleavable linker as describedherein.

Some embodiments include a composition that comprises, consists of, orconsists essentially of an immunoregulatory peptide inhibitor thatcomprises antibodies or a binding fragment thereof, which specificallybinds to P3028 (SEQ ID NO: 185). Some embodiments include antibodies orfragments thereof, which specifically bind to a fragment of P3028 (SEQID NOs: 186 and 187). Exemplary antibodies that bind to P3028 aredescribed in Example 9.

In some embodiments, the antibody or fragment thereof described abovecan be used to inhibit or sequester P3028. In some embodiments, theantibody or fragment thereof specific for P3028 can be administered to apatient having at least one immune cell bound to P3028 so as to unblockat least one of the patient's LFA-1 or IL-2 receptors. In someembodiments, the antibody or fragment thereof can be administered to apatient in need of treatment immunosuppression, as described herein,thereby stimulating or enhancing an immune response of said patient. Forexample, the antibody or fragment thereof can be provided to a patientin need of an inhibition of immunosuppression (e.g., a subject that hascancer or a pathogenic infection such as a bacterial or viralinfection). After providing the antibody or fragment thereof the patientcan be evaluated for an inhibition of immunosupression, which can beaccomplished by determining immune cell infiltration of a tumor or areduction in a bacterial or viral infection, for example, or an improvedimmune response by the PBMCs of said subject.

In other embodiments, the antibody or fragment thereof can be used todetect the presence of P3028, for example, in a biological sample. Theantibody or fragment thereof can be used to detect the formation of acomplex, for example when an immunoregulatory peptide inhibitor (e.g., apeptide SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98 or264-393) is attached to a support, and the antibody is used as a primaryantibody or fragment thereof is used to detect the presence of P3028bound to the inhibitor.

Some embodiments include an antibody or fragment thereof thatspecifically binds to an immunoregulatory peptide inhibitor of P3028(e.g., an antibody or fragment thereof that mimics or has at least 70%,75%, 80%, 85%, 90%, 95%, or 98% identity to one or more of the peptidesof Table 5.1). The antibody or fragment thereof can specifically bind toa peptide that includes at least one of SEQ ID NOs: 1-33, 34, 46-53,64-66, 68, 76, 94-96, 98 or 264-393. In some embodiments, the antibodyor fragment thereof specific for an immunoregulatory peptide inhibitorof P3028 can be used to detect the presence of an immunoregulatorypeptide inhibitor of P3028 in a biological sample. The antibody orfragment thereof specific for an immunoregulatory peptide inhibitor ofP3028 can also be used to detect the formation of a complex, forexample, if P3028 is attached to a support, and the antibody or fragmentthereof is used as a primary antibody to detect the presence of animmunoregulatory peptide inhibitor bound to P3028.

In some embodiments, the antibody or fragment thereof specific for animmunoregulatory peptide inhibitor of P3028 can be used to isolate oridentify the presence of an inhibitor of P3028. For example, theantibody or fragment thereof can be used to purify an inhibitor to beused for stimulating an immune cell of a human, and/or for binding tothe cancer cell of a human.

In some embodiments, the antibody or fragment thereof specific for animmunoregulatory peptide inhibitor of P3028 can be used to detect thepresence of P3028. For example, the antibody or fragment thereofspecific for an immunoregulatory peptide inhibitor of P3028 can be usedfor immunohistochemical staining of a biological sample to detect thepresence of a cancer cell that has been contacted with animmunoregulatory peptide inhibitor. For example, the antibody specificfor an immunoregulatory peptide inhibitor of P3028 can be used in flowcytometry to detect and/or isolate immune or cancer cells that are boundto an immunoregulatory peptide inhibitor. The following section providesmore details on peptide-based immunoregulatory peptide inhibitors.

Peptide-Based Immunoregulatory Peptide Inhibitors

In some embodiments, an isolated peptide that comprises a domain, whichbinds to one or more regions of an immunoregulatory peptide, such asP3028, is provided. The term “isolated” requires that the material beremoved from its original environment (e.g., the natural environment ifit is naturally occurring). For example, a naturally-occurringpolynucleotide present in a living animal is not isolated, but the samepolynucleotide, separated from some or all of the coexisting materialsin the natural system, is isolated. It is also advantageous that thesequences be in purified form. The term “purified” does not requireabsolute purity; rather, it is intended as a relative definition.Isolated proteins have been conventionally purified to electrophoretichomogeneity by Coomassie staining, for example. Purification of startingmaterial or natural material to at least one order of magnitude,preferably two or three orders, and more preferably four or five ordersof magnitude is expressly contemplated. An isolated peptide can exist,for example, in a substantially salt form, crystal form, lyophilizedform, in solution (for example aqueous solution which can includebuffer), and/or in a pharmaceutically carrier or diluent. An isolatedpeptide can exist in a substantially pure form, for example acomposition that includes at least or equal to about 1% of the peptideby weight, for example at least or equal to about 1%, 2, 3, 4, 5, 6, 7,8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 98.5, 99, 99.5, 99.9, 99.99, or 99.999% peptide by weight.

In some embodiments, the isolated immunoregulatory peptide inhibitorsdescribed herein (e.g., a peptide comprising, consisting of, orconsisting essentially of any one of SEQ ID NOs: 1-33, 34, 46-53, 62,64-66, 68, 76, 94-96, 98, 265-393, 583-586, 587-595, or a modified P28Ror P28 core peptide comprising one or more of the modifications of Table5.3 or Table 13 have lengths that are less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values. For example, an immunoregulatory peptide inhibitorconsisting of the sequence (FVKL) (SEQ ID NO: 63) can bind to P3028 witha comparable rampo score to immunoregulatory peptide inhibitors, whichcomprise FVKL (SEQ ID NO: 63), that are 6 to 16 amino acids in length(see FIG. 29 and Example 12). Additionally, amino acids sequences nearan N terminal, C terminal, or exposed loop of a peptide are more likelyto be accessible to potential binding targets rather than incorporatedinto a higher-order peptide structure, thus permitting a peptide of 1100amino acids or less to bind P3028. Therefore, some embodiments of theinvention concern compositions and methods of use thereof (e.g., amethod of binding P3028 or a method of reducing P3028-mediatedimmunosuppression), which comprise, consist of, or consist essentiallyof any one or more of immunoregulatory peptide inhibitors describedherein (e.g., any one or more of the peptides provided in Table 5.1,5.4, 5.5, or 5.6). Desirably these peptides (e.g., any one or more ofthe peptides of Table 5.1, 5.4, 5.5, or 5.6) have lengths that are lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

TABLE 5.1 Sequences and Corresponding Rampo Scores RAMPO SEQ ID SequenceScore 367 KKLDTFFVKLSLMTER 1190 22 KKLDTFFVKLSLMTER 1190 370KKLDTFFVKLSLQTER 1144 23 KKLDTFFVKLSLQTER 1144 364 KKLDTFFVKLSLHTER 104624 KKLDTFFVKLSLHTER 1046 368 KKLDTFFVKLSLNTER 862 25 KKLDTFFVKLSLNTER862 348 KKLDTFFVKLQLFTER 768 15 KKLDTFFVKLQLFTER 768 346KKLDTFFVKLMLFTER 744 16 KKLDTFFVKLMLFTER 744 321 KKLDTFMVKLSLFTER 712 9KKLDTFMVKLSLFTER 712 323 KKLDTFSVKLSLFTER 700 10 KKLDTFSVKLSLFTER 700369 KKLDTFFVKLSLPTER 696 26 KKLDTFFVKLSLPTER 696 343 KKLDTFFVKVSLFTER658 14 KKLDTFFVKVSLFTER 658 355 KKLDTFFVKLSQFTER 651 19 KKLDTFFVKLSQFTER651 372 KKLDTFFVKLSLSTER 635 27 KKLDTFFVKLSLSTER 635 382KKLDTFFVKLSLFNER 599 31 KKLDTFFVKLSLFNER 599 313 KKLDTAFVKLSLFTER 575 7KKLDTAFVKLSLFTER 575 287 KKGDTFFVKLSLFTER 563 94 KKGDTFFVKLSLFTER 563 4KKGDTFFVKLSLFTER 563 383 KKLDTFFVKLSLFPER 551 32 KKLDTFFVKLSLFPER 551319 KKLDTVFVKLSLFTER 547 8 KKLDTVFVKLSLFTER 547 359 KKLDTFFVKLSVFTER 54520 KKLDTFFVKLSVFTER 545 345 KKLDTFFVKLHLFTER 535 308 KKLDQFFVKLSLFTER535 18 KKLDTFFVKLHLFTER 535 6 KKLDQFFVKLSLFTER 535 363 KKLDTFFVKLSLGTER531 100 KKLDTFFVKLSLGTER 531 28 KKLDTFFVKLSLGTER 531 285KKEDTFFVKLSLFTER 528 5 KKEDTFFVKLSLFTER 528 325 KKLDTFVVKLSLFTER 527 11KKLDTFVVKLSLFTER 527 361 KKLDTFFVKLSLATER 525 29 KKLDTFFVKLSLATER 525279 RKLDTFFVKLSLFTER 523 3 RKLDTFFVKLSLFTER 523 349 KKLDTFFVKLTLFTER 52017 KKLDTFFVKLTLFTER 520 324 KKLDTFTVKLSLFTER 517 320 KKLDTFLVKLSLFTER517 13 KKLDTFLVKLSLFTER 517 12 KKLDTFTVKLSLFTER 517 322 KKLDTFQVKLSLFTER511 371 KKLDTFFVKLSLRTER 502 30 KKLDTFFVKLSLRTER 502 381KKLDTFFVKLSLFMER 501 353 KKLDTFFVKLSMFTER 499 21 KKLDTFFVKLSMFTER 499317 KKLDTPFVKLSLFTER 497 334 KKLDTFFVKGSLFTER 495 373 KKLDTFFVKLSLTTER494 298 KKLATFFVKLSLFTER 494 280 TKLDTFFVKLSLFTER 493 284KKDDTFFVKLSLFTER 492 356 KKLDTFFVKLSRFTER 483 273 IKLDTFFVKLSLFTER 483318 KKLDTTFVKLSLFTER 481 357 KKLDTFFVKLSSFTER 478 288 KKHDTFFVKLSLFTER477 305 KKLDMFFVKLSLFTER 475 293 KKQDTFFVKLSLFTER 473 339KKLDTFFVKQSLFTER 470 365 KKLDTFFVKLSLITER 468 315 KKLDTMFVKLSLFTER 467314 KKLDTIFVKLSLFTER 466 268 AKLDTFFVKLSLFTER 466 378 KKLDTFFVKLSLFHER463 354 KKLDTFFVKLSNFTER 462 350 KKLDTFFVKLSAFTER 462 396KKLDTFFVKLSLFTER 460 351 KKLDTFFVKLSHFTER 460 336 KKLDTFFVKMSLFTER 460291 KKMDTFFVKLSLFTER 460 310 KKLDSFFVKLSLFTER 458 275 MKLDTFFVKLSLFTER457 352 KKLDTFFVKLSIFTER 456 329 KKLDTFFPKLSLFTER 456 278QKLDTFFVKLSLFTER 455 289 KKIDTFFVKLSLFTER 454 347 KKLDTFFVKLNLFTER 451296 KKTDTFFVKLSLFTER 451 304 KKLDCFFVKLSLFTER 449 274 LKLDTFFVKLSLFTER449 366 KKLDTFFVKLSLLTER 448 397 KKLDTFIVKLSLFTER 446 374KKLDTFFVKLSLVTER 446 316 KKLDTNFVKLSLFTER 446 398 KKLDTFFVKLSLFTER 445276 NKLDTFFVKLSLFTER 445 302 KKLWTFFVKLSLFTER 443 399 KKLDTFFVKLSLFTER442 281 VKLDTFFVKLSLFTER 442 340 KKLDTFFVKRSLFTER 439 400KKLDTFFVKLSLFTER 437 358 KKLDTFFVKLSTFTER 437 338 KKLDTFFVKPSLFTER 436306 KKLDNFFVKLSLFTER 436 401 KKLDTSFVKLSLFTER 432 402 KNLDTFFVKLSLFTER432 283 KKCDTFFVKLSLFTER 432 375 KKLDTFFVKLSLWTER 430 309KKLDRFFVKLSLFTER 430 300 KKLITFFVKLSLFTER 430 403 KKLDTFFVKLSLFTER 428272 HKLDTFFVKLSLFTER 428 307 KKLDPFFVKLSLFTER 427 282 KKADTFFVKLSLFTER427 404 KKLDTFAVKLSLFTER 426 332 KKLDTFFVKASLFTER 426 405KPLDTFFVKLSLFTER 425 312 KKLDYFFVKLSLFTER 425 406 KKLDTFFVKLSLFTER 424303 KKLYTFFVKLSLFTER 422 311 KKLDWFFVKLSLFTER 418 407 KRLDTFFVKLSLFTER417 299 KKLETFFVKLSLFTER 417 335 KKLDTFFVKISLFTER 415 408KKLDTFFVKLSLFTER 414 409 KKLDTFCVKLSLFTER 411 328 KKLDTFFLKLSLFTER 411410 KKLDTQFVKLSLFTER 410 360 KKLDTFFVKLSWFTER 409 411 KKLDTLFVKLSLFTER408 412 KGLDTFFVKLSLFTER 405 413 KKLTTFFVKLSLFTER 405 387KKLDTFFVKLSLFTDR 404 333 KKLDTFFVKFSLFTER 403 414 KKLDTFFVKLSLFTER 402415 KKLDTFFVKLYLFTER 402 416 KKLDTFFIKLSLFTER 401 417 KMLDTFFVKLSLFTER400 362 KKLDTFFVKLSLCTER 400 342 KKLDTFFVKTSLFTER 399 270EKLDTFFVKLSLFTER 396 418 KHLDTFFVKLSLFTER 394 295 KKSDTFFVKLSLFTER 393286 KKFDTFFVKLSLFTER 393 419 KKLDTFFVKLVLFTER 392 420 KKLDHFFVKLSLFTER391 421 KFLDTFFVKLSLFTER 390 422 KKLDTFFVKLSFFTER 389 277PKLDTFFVKLSLFTER 387 290 KKKDTFFVKLSLFTER 386 95 KKLDGFFVKLSLFTER 386423 KKLMTFFVKLSLFTER 384 344 KKLDTFFVKYSLFTER 382 424 KKLDTFEVKLSLFTER381 425 KKLDTFWVKLSLFTER 380 426 KKLFTFFVKLSLFTER 380 385KKLDTFFVKLSLFVER 380 327 KKLDTFFGKLSLFTER 379 427 KKLDTFFVKLSLFTER 377297 KKVDTFFVKLSLFTER 377 428 KKLDTFFVKLSLFTER 375 379 KKLDTFFVKLSLFIER375 429 KKLDVFFVKLSLFTER 374 386 KKLDTFFVKLSLFWER 374 331KKLDTFFVRLSLFTER 374 292 KKNDTFFVKLSLFTER 374 269 DKLDTFFVKLSLFTER 373430 KKLDTFFVKLSLFTER 371 431 KKLDTFFVKLSGFTER 370 294 KKRDTFFVKLSLFTER370 432 KKLDTFRVKLSLFTER 369 384 KKLDTFFVKLSLFSER 369 271GKLDTFFVKLSLFTER 367 93 GKLDTFFVKLSLFTER 367 391 KKLDTFFVKLSLFTER 366337 KKLDTFFVKNSLFTER 365 330 KKLDTFFRKLSLFTER 365 433 KKLDTFHVKLSLFTER364 434 KKLDTYFVKLSLFTER 364 435 KKLPTFFVKLSLFTER 364 436KKPDTFFVKLSLFTER 361 380 KKLDTFFVKLSLFLER 360 326 KKLDTFFFKLSLFTER 358437 KKLDTFPVKLSLFTER 356 438 KKLDTFFVKLSKFTER 355 439 KKLDTFFVKLSLFTPR351 341 KKLDTFFVKSSLFTER 351 440 KQLDTFFVKLSLFTER 350 441KELDTFFVKLSLFTER 349 442 KKLDTFFVKLSLFTER 348 443 KKLDTFNVKLSLFTER 348444 KKLDTWFVKLSLFTER 348 376 KKLDTFFVKLSLFFER 348 445 KKLDTFFVTLSLFTER347 446 KKLDTGFVKLSLFTER 347 96 KKLDTFGVKLSLFTER 347 447KKLDAFFVKLSLFTER 346 448 KKLQTFFVKLSLFTER 345 449 KKLCTFFVKLSLFTER 344450 KKLDTFFVKLSLFTQR 344 451 KKLSTFFVKLSLFTER 344 452 KKYDTFFVKLSLFTER344 453 SKLDTFFVKLSLFTER 344 454 KLLDTFFVKLSLFTER 343 377KKLDTFFVKLSLFGER 343 455 KKLDTFFVKLSCFTER 342 456 KKLDEFFVKLSLFTER 341457 KKLDTFFVKLCLFTER 341 458 KKWDTFFVKLSLFTER 341 459 KKLDTFFVKLSLFTYR340 460 KKLDTKFVKLSLFTER 337 461 KDLDTFFVKLSLFTER 335 462KKLDTCFVKLSLFTER 335 463 KKLDTFYVKLSLFTER 334 464 KKLDTFFVKLRLFTER 333465 FKLDTFFVKLSLFTER 332 466 KKLDTHFVKLSLFTER 332 467 KILDTFFVKLSLFTER331 468 KTLDTFFVKLSLFTER 331 469 KKLDTFFVQLSLFTER 330 470KKLDTFFVKLPLFTER 328 471 KKLDTFFVKLSLFTKR 324 472 KKLDTFFVKLWLFTER 324473 KKLDTFFVKLKLFTER 323 474 KKLDTFFVKLDLFTER 322 475 KKLDTFFVKLSYFTER320 476 KKLDTFFVKLSLFTER 319 477 KKLDTFFVKLALFTER 318 478KKLDTFFVKLSLFTHR 318 479 KKLHTFFVKLSLFTER 317 480 KKLRTFFVKLSLFTER 317481 KVLDTFFVKLSLFTER 317 482 KKLDTFFVKWSLFTER 316 483 YKLDTFFVKLSLFTER315 484 KKLDLFFVKLSLFTER 311 393 KKLDTFFVKLSLFTEY 311 390KKLDTFFVKLSLFTEN 311 485 KALDTFFVKLSLFTER 309 486 KKLDTRFVKLSLFTER 309487 KKLDTFFVKLSLFTER 308 488 KKLDTFFVHLSLFTER 306 489 KKLDTFFVKLSLFAER305 490 KWLDTFFVKLSLFTER 304 491 KKLLTFFVKLSLFTER 303 492KKLDTFDVKLSLFTER 301 493 KKLDTFFVKLSLFQER 301 494 KYLDTFFVKLSLFTER 301495 KKLDTFFAKLSLFTER 299 496 KKLDTFFTKLSLFTER 298 497 KKLDTFFVKLSPFTER297 388 KKLDTFFVKLSLFTEF 297 498 KKLNTFFVKLSLFTER 296 499KCLDTFFVKLSLFTER 295 500 KKLDDFFVKLSLFTER 295 501 KKLDIFFVKLSLFTER 293502 KKLDTFFVKHSLFTER 293 392 KKLDTFFVKLSLFTET 292 503 KKLDTFFVKLSLYTER291 389 KKLDTFFVKLSLFTEK 291 504 KKLDFFFVKLSLFTER 290 505KKLDTFFVKLILFTER 289 99 KKLDTFFVKLGLFTER 288 506 KKLDTFFVKKSLFTER 285507 WKLDTFFVKLSLFTER 284 508 KKLDTFFVKCSLFTER 283 509 KKLDTFFVMLSLFTER283 510 KSLDTFFVKLSLFTER 281 511 KKLDTFFVSLSLFTER 274 512KKLKTFFVKLSLFTER 274 513 KKLDTFFQKLSLFTER 271 514 KKLDTFFVKLSLFYER 270515 KKLGTFFVKLSLFTER 264 33 KKLDTFFVKLSLFRER 264 516 KKLDTFFVKLSLFTER260 517 KKLDTFFVKLSLFKER 259 518 KKLDTFFVNLSLFTER 256 519KKLDTFFCKLSLFTER 254 520 KKLDTFFVKLSLFCER 254 521 KKLDTFFVKLSLFTEV 254264 KKLDTFFKKLSLFTER 253 522 KKLDTFFVKLFLFTER 250 523 KKLDTFFVVLSLFTER248 524 KKLDTFFVKLSLFTMR 247 525 KKLDTFFVKLSLFTLR 246 526KKLDTFFVWLSLFTER 245 527 KKLDTFFVELSLFTER 240 528 KKLDTFFVKLSLFTEH 239529 KKLDTFFVKLSLFTEM 238 530 KKLDKFFVKLSLFTER 237 531 KKLDTFFVKLSLFTRR237 532 KKLDTFFVKLELFTER 234 533 KKLDTFFVKLSLFTEP 234 534KKLDTFFVPLSLFTER 233 101 KKLDTFFVKLSLFTGR 233 535 KKLDTFKVKLSLFTER 232536 KKLDTEFVKLSLFTER 229 537 KKLDTFFWKLSLFTER 228 538 KKLDTFFVKLSLFTEA226 539 KKLDTFFVKLSLFTWR 226 540 KKLDTFFMKLSLFTER 221 541KKLDTFFVCLSLFTER 220 542 KKLDTFFVKLSLKTER 220 543 KKLDTFFVKLSLFTEG 218544 KKLDTFFVKLSLFTEL 217 545 KKLDTFFSKLSLFTER 216 546 CKLDTFFVKLSLFTER215 547 KKLDTFFHKLSLFTER 213 548 KKLDTFFVKLLLFTER 213 549KKLDTFFYKLSLFTER 211 550 KKLDTFFNKLSLFTER 203 551 KKLDTFFVKLSLFTEW 202552 KKLDTFFVYLSLFTER 198 553 KKLDTDFVKLSLFTER 193 554 KKLDTFFVALSLFTER191 555 KKLDTFFVILSLFTER 190 98 KKLDTFFVGLSLFTER 188 97 KKLDTFFVGLSLFTER188 556 KKLDTFFVKLSLFTCR 185 557 KKLDTFFVKLSLFTES 184 558KKLDTFFVKLSLFTEI 176 559 KKLDTFFVKLSLFTEC 175 560 KKLDTFFVFLSLFTER 174561 KKLDTFFVKLSLFTAR 174 562 KKLDTFFVLLSLFTER 166 563 KKLDTFFVKLSLFTSR165 564 KKLDTFFVKLSLFTIR 163 565 KKLDTFFVKLSLFTVR 163 566KKLDTFFVKLSLFTNR 161 567 KKLDTFFVKLSLFDER 159 568 KKLDTFFVKLSLFTTR 152569 KKLDTFFVDLSLFTER 149 570 KKLDTFFEKLSLFTER 139 571 KKLDTFFVKLSLFTFR137 572 KKLDTFFVKLSLFTED 133 573 KKLDTFFVKLSLFTEQ 133 574KKLDTFFDKLSLFTER 122 575 KKLDTFFVKLSLDTER 112 576 KKLDTFFVKLSLFEER 110577 KKLDTFFVKLSLFTEE 107 578 KKLDTFFVKDSLFTER 102 579 KKLDTFFVKLSLETER98 580 KKLDTFFVKLSDFTER 89 581 KKLDTFFVKLSEFTER 82 582 KKLDTFFVKESLFTER81

As shown in Example 12, at least 31 single amino acid substitutions ofP28R shown in Table 6.1 (SEQ ID NOs: 3-34) bind to P3028 with a higherrampo score than P28R. Additionally at least 4 single substitutions ofglycine residues for residues of P28R (SEQ ID NOs: 94-96 and 98) bind toP3028 with a rampo scores at least comparable to P28R, for example arampo score greater than about 500. Additionally at least 129 singleamino acid substitutions bind to P3028 with a rampo score at leastsubstantially equal to (i.e., at least 98% of) P28R, as shown in Table6.2 (SEQ ID NOs: 268-393). Additionally, truncations of at least the Nterminal arginine of P28R (SEQ ID NO: 34), and up to the first 8 Cterminal amino acids of P28R (SEQ ID NOs: 46-53) provide peptides withrampo scores at least comparable to P28R. Additionally, at least someinternal amino acid residue deletions of P28 (SEQ ID NOs: 64-66, 68, 76)provide peptides with ramp scores at least comparable to P28R. Thus,contemplated herein are peptides that include substitutions of P28R thatinclude combinations of two or more of the substitutions of SEQ ID NOs:3-34. Moreover, contemplated herein are peptides that include at leastone deletion of P28R as in SEQ ID NOs: 34, 46-53, 64-66, 68, and/or 74,and at least one substitution (of a non-deleted residue) of P28R as inSEQ ID NOs: 3-34, 94-96, 98 and/or 268-393.

Accordingly, some embodiments concern compositions that comprise,consist of, or consist essentially of an immunoregulatory peptideinhibitor that comprises, consists of, or consists essentially ofFormula (I):

Formula (I): (SEQ ID NO: 166) XX₁VKX₂X₃X₄.

wherein X is an optional sequence, and can be KKLDT (SEQ ID NO: 167),RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170),KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253),RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO: 256),RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO: 172),KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO: 261),KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ, EDT,EDQ, DT, DQ, T, or Q, or absent.

X₁ can be one of FF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT, AL, VF, VM,VS, VV, VT, or VL.

X₂ can be one of LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH.

X₃ can be one of LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT,QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT,VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT,MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN,QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN,VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP,LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP,QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP,VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815),LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR,QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR,VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR.

X₄ is an optional sequence, and can be ER, or E, or absent.

In some embodiments, if X is absent, X₁ is FF, and X₂ is LS.

In some embodiments, the isolated peptide comprising Formula (I) has alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Some embodiments concern compositions that comprise, consist of, orconsist essentially of an immunoregulatory peptide inhibitor thatcomprises, consists of, or consists essentially of Formula (II):

Formula (II): (SEQ ID NO: 173) X₂₀TFFVKLSX₂₁X₂₂

wherein X₂₀ is an optional sequence, and can be KKLD (SEQ ID NO: 174),RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO: 177),KLD, LD, or D, or absent.

X₂₁ is an optional sequence, and can be LFT, LMT, LQT, LHT, LNT, LPT,LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT,VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT,MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN,LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN,VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN,MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP,QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP,VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP,MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR,LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR,VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR,MGR, MAR, or MRR, or absent.

X₂₂ is an optional sequence, and can be ER, or E, or absent.

In some embodiments, the isolated peptide comprising Formula (II) has alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Some embodiments concern compositions that comprise, consist of, orconsist essentially of an immunoregulatory peptide inhibitor thatcomprises, consists of, or consists essentially of Formula (III):

Formula (III): (SEQ ID NO: 178) X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄

wherein X₃₀ is an optional sequence, and can be KKLDTF (SEQ ID NO: 179),KLDTF (SEQ ID NO: 180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent.

X₃₁ is an optional sequence, and can be F, S, M, V, T, or L, or absent.In some embodiments, X₃₁ is F.

X₃₂ can be S, Q, M, T, or H. In some embodiments, X₃₂ is S.

X₃₃ can be F, M, Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ isF.

X₃₄ is an optional sequence, and can be R, or absent.

In some embodiments, the isolated peptide comprising Formula (III) has alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Some embodiments concern compositions that comprise, consist of, orconsist essentially of an immunoregulatory peptide inhibitor thatcomprises, consists of, or consists essentially of Formula (VII):

Formula (VII): (SEQ ID NO: 394)X₇₀₀K X₇₀₁X₇₀₂X₇₀₃ X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂,

wherein X₇₀₀ is an optional sequence, and can be K, A, D, E, G, H, I, L,M, N, P, Q, R, T, or V, or absent.

X₇₀₁ is an optional sequence, and can be L, A, C, D, E, F, G, H, I, K,M, N, Q, R, S, T, or V, or absent.

X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W, or Y, orabsent.

X₇₀₃ is an optional sequence, and can be T, C, M, N, P, Q, R, S, W, orY,or absent.

X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent.

X₇₀₅ is an optional sequence, and can be F, L, M, Q, S, T or V, orabsent.

X₇₀₆ is an optional sequence, and can be V, F, G, L, P, or R, or absent.

X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M, N, P, Q, R,S, T, V, or Y, or absent.

X₇₀₈ is an optional sequence, and can be S, H, M, N, Q, or T, or absent.

X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N, Q, R, S, T,V, or W, or absent.

X₇₁₀ is an optional sequence, and can be F, A, C, G, H, I, L, M, N, P,Q, R, S, T, V, or W, or absent.

X₇₁₁ is an optional sequence, and can be T, F, G, H, I, L, M, N, P, S,V, or W, or absent.

X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent.

In some embodiments, the isolated peptide comprising Formula (VII) has alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Some embodiments concern compositions that comprise, consist of, orconsist essentially of an immunoregulatory peptide inhibitor thatcomprises, consists of, or consists essentially of Formula (VIII):

Formula (VIII): (SEQ ID NO: 395) X₈₀₀K X₈₀₁K X₈₀₂E X₈₀₃

wherein X₈₀₀ is K, A, D, E, G, H, I, L, M, N, P, Q, R, T, V, or K, orabsent.

X₈₀₁ is LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597), EDTFFV (SEQ IDNO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO: 600), LDTVFV (SEQID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ ID NO: 603), LDTFVV(SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQ ID NO: 606),LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK (SEQ ID NO:609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611), DDTFFV (SEQ IDNO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO: 614), IDTFFV (SEQID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ ID NO: 617), NDTFFV(SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQ ID NO: 620),SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV (SEQ ID NO:623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625), LITFFV (SEQ IDNO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO: 628), LYTFFV (SEQID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ ID NO: 631), LDNFFV(SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQ ID NO: 634),LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV (SEQ ID NO:637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639), LDTNFV (SEQ IDNO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO: 642), LDTFQV (SEQID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ ID NO: 645), LDTFFL(SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQ ID NO: 648),LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV (SEQ ID NO:651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653), LDTLFV (SEQ IDNO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO: 656), LDHFFV (SEQID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ ID NO: 659), LDTFWV(SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQ ID NO: 662),LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV (SEQ ID NO:665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667), LDTFPV (SEQ IDNO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO: 670), LDTGFV (SEQID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ ID NO: 673), LCTFFV(SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQ ID NO: 676),LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV (SEQ ID NO:679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681), LDTHFV (SEQ IDNO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO: 684), LDLFFV (SEQID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ ID NO: 687), LDTFDV(SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQ ID NO: 690),LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV (SEQ ID NO:693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695), LDTFFQ (SEQ IDNO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO: 698), LDKFFV (SEQID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ ID NO: 701), LDTFFW(SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQ ID NO: 704),LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN (SEQ ID NO:707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709), LDTFFD (SEQ IDNO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712), TFFV (SEQ IDNO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L, or absent;

wherein X₈₀₂ is LSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT(SEQ ID NO: 717), LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT(SEQ ID NO: 720), LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT(SEQ ID NO: 723), LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT(SEQ ID NO: 726), LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST(SEQ ID NO: 729), LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT(SEQ ID NO: 732), LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR(SEQ ID NO: 735), LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT(SEQ ID NO: 738), GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT(SEQ ID NO: 741), NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT(SEQ ID NO: 744), RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT(SEQ ID NO: 747), YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT(SEQ ID NO: 750), LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT(SEQ ID NO: 753), LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT(SEQ ID NO: 756), LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT(SEQ ID NO: 759), LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT(SEQ ID NO: 762), LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG(SEQ ID NO: 765), LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL(SEQ ID NO: 768), LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV(SEQ ID NO: 771), LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT(SEQ ID NO: 774), LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT(SEQ ID NO: 777), LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT(SEQ ID NO: 780), LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT(SEQ ID NO: 783), LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT(SEQ ID NO: 786), WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ(SEQ ID NO: 789), LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT(SEQ ID NO: 792), LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT(SEQ ID NO: 795), LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC(SEQ ID NO: 798), LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT(SEQ ID NO: 801), LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT(SEQ ID NO: 804), LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET(SEQ ID NO: 807), LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT(SEQ ID NO: 810), SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT,LSL, LT, or T, or absent; and

wherein X₈₀₃ is R, F, K, N, R, T, or Y, or absent.

In some embodiments, the isolated peptide comprising Formula (VIII) hasa length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Some embodiments concern compositions that comprise, consist of, orconsist essentially of an immunoregulatory peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in Table 5.1. In some embodiments, the isolatedpeptide from Table 5.1 used in these compositions has a length that isless than or equal to 1100 amino acids, for example, less than or equalto 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76,77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94,95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109,110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123,124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137,138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250,260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600,650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids,including ranges between any two of the listed values.

In some embodiments, the peptide comprises one of SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96 or 98. Again, this isolated peptide can havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Embodiments of the invention also include immunoregulatory peptideinhibitors that have a specific affinity to P3028 sequences orstructures. In some embodiments, the immunoregulatory peptide inhibitorshave specific affinity to P3028 sequences or structures as measured by arampo assay in which the immunoregulatory peptide inhibitors are affixedto a solid phase, P3028 is added, and the enzymatic activity of a ramposecondary antibody is measured so as to detect binding (see Example 12).In some embodiments, the immunoregulatory peptide inhibitors bind toP3028 structures or sequences with a rampo score that is at leastsubstantially equal to the rampo score of P28R (see Example 12, Table6.2). Preferably, the immunoregulatory peptide inhibitors have aspecific affinity to P3028 by this rampo assay of at least or equal toabout 300 rampo units, for example, at least or equal to about 300, 310,320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450,460, 470, 480, 490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590,600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730,740, 750, 760, 770, 780, 790, 800, 820, 840, 860, 880, 900, 920, 940,960, 980, 1000, 1020, or 1040 rampo units, including ranges between anytwo of the listed values. In some embodiments, the immunoregulatorypeptide inhibitors bind to P3028 structures or sequences with a ramposcore of at 500 (see Example 12, Table 6.1). Exemplary peptides withaffinity to P3028 are provided in Example 12 (see Tables 6.1, 6.2, andFIGS. 29-30).

Similarly, embodiments include isolated immunoregulatory peptideinhibitors that have an affinity to any one or more of theimmunoregulatory peptides listed in Tables 1-4 (SEQ ID NOs: 183-184 and188-246). In some embodiments, the immunoregulatory peptide inhibitorshave specific affinity to any one or more of the immunoregulatorypeptides listed in Tables 1-4 (SEQ ID NOs: 183-184 and 188-246), asmeasured by a rampo assay in which the immunoregulatory peptideinhibitors are affixed to a solid phase, any one or more of theimmunoregulatory peptides listed in Tables 1-4 (SEQ ID NOs: 183-184 and188-246) is added, and the enzymatic activity of a rampo secondaryantibody is measured so as to detect binding. For example, aspects ofthe invention include any peptide provided in Table 5.1 and any of themethods described herein can be practiced using one or more of thepeptides described in Table 5.1. Preferably, the immunoregulatorypeptide inhibitors have a specific affinity to any one or more of theimmunoregulatory peptides listed in Tables 1-4 (SEQ ID NOs: 183-184 and188-246) by this rampo assay of at least or equal to about 300 rampounits, for example, at least or equal to about 300, 310, 320, 330, 340,350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480,490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620,630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730, 740, 750, 760,770, 780, 790, 800, 820, 840, 860, 880, 900, 920, 940, 960, 980, 1000,1020, or 1040 rampo units, including ranges between any two of thelisted values.

Peptide Sequence Variations

A number of sequence variations to the immunoregulatory peptideinhibitor P28R (KKLDTFFVKLSLFTER; SEQ ID NO: 2) have been shown to haveimmunostimulatory activity and/or cytotoxicity to tumor cells (seeExamples 37-40). Without being limited by any theory, SEQ ID NO: 2 andvariations of SEQ ID NO: 2 as described in Table 5.3 for example, one ormore of the peptides of Table 5.4 can be useful for binding peptide 3028(SEQ ID NO: 185), binding a peptide or albumin fragment that comprisesSEQ ID NO: 185, binding any one or more of the peptides listed in Tables1-4, directly stimulating immune cells, and/or killing tumor cells inaccordance with some embodiments herein (see Examples 36-40). As such,in some embodiments, a immunoregulatory peptide inhibitor peptidecomprises, consists of, or consists essentially of an amino acidsequence with one or more of the modifications to SEQ ID NO: 2 as shownin Table 5.3, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10modifications, for example, 1-2, 1-3, 1-4, 1-5, 1-6, 1-7, 1-8, 1-9,1-10, 2-3, 2-4, 2-5, 2-6, 2-7, 2-8, 2-9, 2-10, 3-4, 3-5, 3-6, 3-7, 3-8,3-9, 3-10, 4-5, 4-6, 4-7, 4-8, 4-9, 4-10, 5-6, 5-7, 5-8, 5-9, 5-10, 6-7,6-8, 6-9, 6-10, 7-8, 7-9, 7-10, 8-9, 8-10, or 9-10 variations. Theinhibitor peptide can further comprise a further variation at one ormore of positions 1, 3-4, 12-14, or 16 in SEQ ID NO: 2, wherein thefurther variation comprises any amino acid or the absence of an aminoacid, for example, 1, 2, 3, 4, 5, 6, or 7 further variations:

TABLE 5.3 Position in KKLDTFFVKLSLFTER Exemplary Amino (SEQ ID NO: 2)Type of Variation Acids for Variations K1 Any type of amino acid Anyamino acid or absent K2 Positive charged amino acid R, H, K L3 Any typeof amino acid Any amino acid or absent D4 Any type of amino acid Anyamino acid or absent T5 Polar uncharged amino acid S, T, N, Q F6Hydrophobic or uncharged polar A, V, I, L, F, Y, W, S, amino acid T, N,Q F7 Hydrophobic or uncharged polar A, V, I, L, F, Y, W, S, amino acidT, N, Q V8 Hydrophobic, non-aromatic carbon A, V, I, L chain amino acidsthat are not M K9 Positively charged amino acids, T, R, H, K, T, Q, Y Q,or Y L10 Any type of amino acid except R, H, K, S, T, N, Q, C,negatively charged U, G, P, A, V, I, L, M, F, Y, W S11 Polar unchargedamino acids S, T, N, Q L12 Any type of amino acid except R, H, K, S, T,N, Q, C, negatively charged U, G, P, A, V, I, L, M, F, Y, W F13 Any typeof amino acid except R, H, K, S, T, N, Q, C, negatively charged U, G, P,A, V, I, L, M, F, Y, W T14 Any type of amino acid except R, H, K, S, T,N, Q, C, negatively charged U, G, P, A, V, I, L, M, F, Y, W E15Negatively charged amino acids D, E

In some embodiments, the varied peptide does not comprise a M atposition 8. In some embodiments, the varied peptide does not comprise aM at position 9. In some embodiments, the varied peptide does notcomprise a M at position 15. In some embodiments, the modified peptidedoes not comprise a M at any of positions 8, 9, or 15.

Accordingly, in some embodiments, the peptide inhibitor comprising avariation of P28R comprises, consists essentially of, or consists of apeptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,  Formula(IX)

-   -   wherein X₉₀₁ is any amino acid or absent,    -   X₉₀₂ is a positively charged amino acid, F, or N,    -   X₉₀₃ is any amino acid,    -   X₉₀₄ is any amino acid,    -   X₉₀₅ is a polar uncharged amino acid, R, Y, or W,    -   X₉₀₆ is a hydrophobic or uncharged polar amino acid,    -   X₉₀₇ is a hydrophobic or uncharged polar amino acid,    -   X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acid that        is not M or F,    -   X₉₀₉ is a positively charged amino acid, T, Q, or Y,    -   X₉₁₀ is any amino acid that is not negatively charged,    -   X₉₁₁ is a polar uncharged amino acid or H,    -   X₉₁₂ is any amino acid that is not negatively charged,    -   X₉₁₃ is any amino acid that is not negatively charged,    -   X₉₁₄ is any amino acid that is not negatively charged,    -   X₉₁₅ is a negatively charged amino acid, Y, or Q,    -   X₉₁₆ is any amino acid that is not negatively charged, and    -   X₉₁₇ is one or more positively charged amino acids or is absent.        Optionally, X₉₀₁ comprises a positively charged amino acid.        Optionally, X₉₀₁ is an R or K.        Optional, X₉₁₇ comprises or consists of RR.

A number of peptide inhibitors based on variation of peptides describedherein have been shown to stimulate immune cells (see Example 36).Exemplary varied peptides are shown in Table 5.4. Accordingly, in someembodiments, the peptide inhibitor comprises, consists of, or consistsessentially of a peptide of Table 5.4. Additional exemplary variedpeptides shown to have low binding to P3028 (see Example 36) or lowstimulation of healthy PBMC's in healthy serum (see Example 37) areshown in Tables 5.5 and 5.6. In some embodiments, a peptide comprising,consisting of, or consisting essentially of a peptide of Table 5.4, 5.5,or 5.6 is provided.

TABLE 5.4 Peptides with “high” binding to P3028based on positional scans Amino Acid Sequence (variation(s) toMay also be SEQ ID NO: 2 are referred SEQ ID NO: underlined) to as: 583KKLDTFFVKLSLMTER 30677 584 KKLDTFFVKLQLFTER 30678 585 KKLDTVMVKLQLMTER30680 586 RKLDTFFVKLSLFTERRR 32814

TABLE 5.5 Peptides with “low” binding to P3028 based on positional scansAmino Acid Sequence (variation(s) to SEQ ID NO: 2 are May also beSEQ ID NO: underlined) referred to as: 587 KSLDTFFVKLSLFTER 30684 588KKLDTFFVKLSLFTFR 30685 589 KKLDTFFVYLSLFTER 31135 590 KKLDTFFVNLSLFTER31136 591 KKLDTFFVDLSLFTER 31138

TABLE 5.6 Additional modification of P28R Amino Acid Sequence(variation(s) to May also be SEQ ID NO: 2 are referred SEQ ID NO:underlined) to as: 592 KKLDTFFPKLSLFTER 32251 593 KKLDTFMVKLSQHTER 32665594 KKLDTFFVKLSLFTER(C(PEG24)) 32819 595 KKLDQFFVKLSQHNER 32815

Embodiments of the invention also include peptides and proteins withidentity to an isolated immunoregulatory peptide inhibitor describedherein. The term “identity” is meant to include nucleic acid or proteinsequence homology or three-dimensional homology. Several techniquesexist to determine nucleic acid or peptide sequence homology and/orthree-dimensional homology to peptides. These methods are routinelyemployed to discover the extent of identity that one sequence, domain,or model has to a target sequence, domain, or model. A vast range offunctional immunoregulatory peptide inhibitors (e.g., animmunoregulatory peptide inhibitor for P3028 sequence or structures) canincorporate features of peptide inhibitors disclosed herein, thusproviding for a vast degree of identity to the immunoregulatory peptideinhibitors of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98,264-393, 583-586, or 589. For example, a fusion protein having a smallregion of an inhibitor can exhibit a low degree of overall identity toan immunoregulatory peptide inhibitor of SEQ ID NOs: 1-33, 34, 46-53,64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589, yet retain theability to function as inhibitor (e.g., an inhibitor of P3028, such as amolecule that binds to P3028), or to enhance immune cell stimulation viathe LFA-1 and/or IL-2 receptor (e.g., modulate, upregulate or downregulate a marker of the immune system or immunosuppression, such asreducing a P3028-mediated inhibition of immune cell proliferation,spreading, migration, or NK-cell cytotoxicity), or to enhance immunecell stimulation. Thus, embodiments of the invention can have from 1%identity to 100% identity to the sequences of SEQ ID NOs: 1-33, 34,46-53, 62, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589. That is,embodiments can have at least or equal to about, 1%, 2%, 3%, 4%, 5%, 6%,7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%,22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%,36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%,50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%,64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 73%, 74%, 76%, 77%,78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%,92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to any one ofSEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586,or 589. Preferably, these peptides or modified peptides also retain theability to modulate the immune system (e.g., modulate, upregulate ordown regulate a marker of the immune system or immunosuppression, suchas reducing a P3028-mediated inhibition of immune cell proliferation,spreading, migration, or NK-cell cytotoxicity).

Embodiments also include compositions that comprise multimers ofisolated immunoregulatory peptide inhibitors and/or isolatedimmunoregulatory peptide inhibitors bound to a support. Some embodimentsinclude compositions that comprise multimers of immunoregulatory peptideinhibitors that include multiple copies of a single immunoregulatorypeptide inhibitor. Some embodiments include compositions that comprisemultimers that include two or more different immunoregulatory peptideinhibitors. Some multimers include at least or equal to twoimmunoregulatory peptide inhibitors, for example 2, 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 45, 50, 55, 60, 65,70, 75, 80, 85, 90, 95, 99, 100, or 101 immunoregulatory peptideinhibitors. In some embodiments, the multimers are of the sameimmunoregulatory peptide inhibitor and in other embodiments, themultimers are of different immunoregulatory peptide inhibitors.Accordingly, some embodiments concern compositions that comprise one ormore immunoregulatory peptide inhibitors and in some embodiments, theone or more immunoregulatory peptide inhibitor are multimers of the samemolecule.

Methods of Making Peptide-Based Immunoregulatory Peptide Inhibitors

Many methods of making peptides are known in the art. Examples ofmethods of making peptides can be found in U.S. Pat. No. 6,495,674,hereby expressly incorporated by reference in its entirety. In someembodiments, peptide inhibitors are chemically synthesized. Chemicalsynthesis of peptides is also well-known. For example, solid phasechemical synthesis can be used to produce peptides of up to at leastabout 100 amino acids in length. Accordingly, in some embodiments, theimmunoregulatory peptide inhibitor is a synthetic peptide.

In other embodiments, immunoregulatory peptide inhibitors are preparedby recombinant DNA technology using techniques well known in the art.Such methods can be used to construct expression vectors containingnucleotide sequences encoding an immunoregulatory peptide inhibitor, forexample, and appropriate transcriptional and translational controlsignals. These methods can include, for example, in vitro recombinantDNA techniques, synthetic techniques, and in vivo genetic recombination.Alternatively, RNA capable of encoding a peptide inhibitor can bechemically synthesized using, for example, synthesizers. See, forexample, the techniques described in Oligonucleotide Synthesis, 1984,Gait, M. J. ed., IRL Press, Oxford, which is incorporated by referenceherein in its entirety. Alternatively, a DNA or RNA encoding a peptideor protein substantially longer that the peptide inhibitor can beprovided, in which the peptide inhibitor is flanked by protease targetsites, thus producing the peptide inhibitor from a larger peptide orprotein. Exemplary proteases include thrombin, trypsin, chymotrypsin,LysC, GluC, and AspN. Alternatively, a DNA or RNA encoding two or morecopies of the peptide inhibitor can be provided, in which the peptideinhibitors are flanked by protease target sites, thus producing thepeptide inhibitor from a larger peptide or protein. Thus, in someembodiments, the peptide inhibitor of P3028 is produced by a ribosome.

In several embodiments, the immunoregulatory peptide inhibitors areexpressed in a cell line. For example, some cells are provided a nucleicacid encoding one or more immunoregulatory peptide inhibitors, saidcells are made to express the peptides of SEQ ID NOs: 1-33, 34, 46-53,64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one or more ofthe peptides provided in Table 5.1 and the immunoregulatory peptideinhibitors are isolated and/or purified. Exemplary nucleic acids arelisted in Table 5.2, SEQ ID NOs: 102-165.

A variety of host-expression vector systems can be utilized to expressinhibitor peptides of some embodiments of the invention. Where theimmunoregulatory peptide inhibitor is a soluble peptide, it can berecovered from the culture, i.e., from the host cell in cases where thepeptide or polypeptide is not secreted, and from the culture media incases where the peptide or polypeptide is secreted by the cells.However, the expression systems also encompass engineered host cellsthat express the peptide or functional equivalents in situ, i.e.,anchored in the cell membrane. Purification or enrichment of the peptidefrom such expression systems can be accomplished using appropriatedetergents and lipid micelles and methods well known to those skilled inthe art. However, such engineered host cells themselves can be used insituations where it is important not only to retain the structural andfunctional characteristics of the peptide, but to assess biologicalactivity, e.g., in drug screening assays.

The expression systems that can be used for purposes of the inventioninclude, but are not limited to, microorganisms such as bacteria (e.g.,E. coli or B. subtilis) transformed with recombinant bacteriophage DNA,plasmid DNA or cosmid DNA expression vectors containing nucleotidesequences encoding inhibitor peptides; yeast (e.g., Saccharomyces,Pichia) transformed with recombinant yeast expression vectors containingthe nucleotide sequences encoding inhibitor peptides; insect cellsystems infected with recombinant virus expression vectors (e.g.,baculovirus) containing sequences encoding inhibitor peptides; plantcell systems infected with recombinant virus expression vectors (e.g.,cauliflower mosaic virus, CaMV; tobacco mosaic virus, TMV) ortransformed with recombinant plasmid expression vectors (e.g., Tiplasmid) containing nucleotide sequences encoding inhibitor peptides;mammalian cell systems (e.g., COS, CHO, BHK, 293, 3T3) harboringrecombinant expression constructs containing promoters derived from thegenome of mammalian cells (e.g., metallothionein promoter) or frommammalian viruses (e.g., the adenovirus late promoter; the vacciniavirus 7.5K promoter); or cell-free expression systems, which can includecell lysates or fractions thereof, and nucleic acids encoding theinhibitor peptides.

In bacterial systems, a number of expression vectors can beadvantageously selected depending upon the use intended for the peptidebeing produced. For example, when a large quantity of such a peptide isto be produced, for the generation of pharmaceutical compositions or forraising antibodies to the peptide, for example, vectors which direct theexpression of high levels of fusion protein products that are readilypurified can be desirable. Such vectors include, but are not limited, tothe E. coli expression vector pUR278 (Ruther et al., EMBO J., 2:1791(1983), in which the inhibitor peptide coding sequence can be ligatedindividually into the vector in frame with the lacZ coding region sothat a fusion protein is produced; pIN vectors (Inouye & Inouye, NucleicAcids Res., 13:3101-3109 (1985); Van Heeke & Schuster, J. Biol. Chem.,264:5503-5509 (1989)); and the like. pGEX vectors can also be used toexpress foreign polypeptides as fusion proteins with glutathioneS-transferase (GST). In general, such fusion proteins are soluble andcan be purified from lysed cells by adsorption to glutathione-agarosebeads followed by elution in the presence of free glutathione. The PGEXvectors are designed to include thrombin or factor Xa protease cleavagesites so that the cloned target gene product can be released from theGST moiety.

In an insect system, Autographa californica nuclear polyhedrosis virus(AcNPV) is used as a vector to express foreign genes. The virus grows inSpodoptera frugiperda cells. The peptide coding sequence can be clonedindividually into non-essential regions (for example the polyhedringene) of the virus and placed under control of an AcNPV promoter (forexample the polyhedrin promoter). Successful insertion of peptide codingsequence will result in inactivation of the polyhedrin gene andproduction of non-occluded recombinant virus, (i.e., virus lacking theproteinaceous coat coded for by the polyhedrin gene). These recombinantviruses are then used to infect Spodoptera frugiperda cells in which theinserted gene is expressed. (E.g., see Smith et al., J. Virol. 46: 584(1983); and Smith, U.S. Pat. No. 4,215,051).

In mammalian host cells, a number of viral-based expression systems canbe utilized. In cases where an adenovirus is used as an expressionvector, the nucleotide sequence of interest can be ligated to anadenovirus transcription/translation control complex, e.g., the latepromoter and tripartite leader sequence. This chimeric gene can then beinserted in the adenovirus genome by in vitro or in vivo recombination.Insertion in a non-essential region of the viral genome (e.g., region E1or E3) will result in a recombinant virus that is viable and capable ofexpressing the peptide in infected hosts. (E.g., see Logan & Shenk,Proc. Natl. Acad. Sci. USA 81:3655-3659 (1984)). Specific initiationsignals can also be required for efficient translation of insertednucleotide sequences encoding peptides. These signals include the ATGinitiation codon and adjacent sequences.

In cell free systems, cellular extracts, or fractions thereof areprovided for the translation of nucleic acids into polypeptides invitro. Cell free systems can include, for example E. coli extracts,yeast extracts. The extracts can be lysates. The extracts can bepurified, for example, to enrich for ribosomes and/or to removeundesired materials such as debris or host genomic DNA. Nucleic acidsencoding immunoregulatory peptide inhibitors in cell-free systems caninclude plasmid DNA, linear DNA, or RNA.

In some embodiments, immunoregulatory peptide inhibitors are isolated orpurified after expression. Isolation or purification can includeaffinity purification. In some embodiments, the peptide product of theexpression system includes an affinity tag, for example GST separated bya cleavable linker, for example a thrombin or factor Xa proteasecleavage site. After affinity purification, the affinity tag can becleaved, producing a substantially pure peptide that does not have anaffinity tag or cleavage site. In some embodiments, purification resultsin a composition that is at least or equal to about 1, 2, 3, 4, 5, 6, 7,8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 98.5, 99, 99.5, 99.9, 99.99, or 99.999% peptide by weight. Thesection below provides more information on pharmaceutically acceptablecarriers and diluents that can be used with the embodiments describedherein.

D Amino Acids and Non-Natural Amino Acids

Some embodiments include compositions that comprise, consist, or consistessentially of one or more immunoregulatory peptide inhibitors thatinclude at least one D amino acid. With the exception of glycine, thechiral carbon of an amino acid can exist as the D or the L isomer.Typically, amino acids synthesized by ribosomes are in the Lconfiguration. However, peptides that include D amino acids, or acombination of D and L amino acids can have activity, for example asligands or inhibitors. For example, a peptide including at least one Damino acid can bind to the P3028 sequence/structure and inhibit theability of the P3028 sequence/structure to bind to the LFA-1 receptorand/or the IL-2 receptor.

Accordingly, some embodiments include immunoregulatory peptideinhibitors that comprise at least one non-natural amino acid.Non-natural amino acids include amino acids having R groups other thanthe R group of the 20 amino acids encoded by the standard genetic code.Non-natural amino acids can exist in the L or D configuration. Thus,some embodiments include peptides having non-natural amino acids in theD configuration and/or the L configuration. Exemplary non-natural aminoacids are described in U.S. Pat. Nos. 8,153,758, 7,888,533, 6,344,483,each of which is expressly incorporated by reference in its entiretyherein. Some embodiments concern a composition that comprises, consistsof, or consists essentially of one or more of the immunoregulatorypeptide inhibitors described herein (e.g., an immunoregulatory peptideinhibitor of the P3028 sequence/structure, such as one or more of theimmunoregulatory peptide inhibitors provided by of SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13, wherein said immunoregulatory peptide inhibitorcomprises at least one D amino acid. Similarly, some embodiments concerna composition comprising immunoregulatory peptide inhibitor of the P3028sequence/structure, wherein said immunoregulatory peptide inhibitors(e.g., any one or more of the immunoregulatory peptide inhibitorsprovided by of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98,264-393, 583-586, or 589 or any one or more of the peptides provided inTable 5.1, 5.4, 5.5, 5.6, or any variation or combination of variationsof P28R or P28 core as provided in Tables 5.3 and 13 comprises at leastone non-natural amino acid. Further embodiments include a compositioncomprising an immunoregulatory peptide inhibitor (e.g., any one or moreof the immunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33,34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any oneor more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13, wherein each non-glycine amino acid of theimmunoregulatory peptide inhibitor is a D amino acid.

The crystal structure of the IL-2 receptor (CD25) has been solved, andcomputer modeling of P3028 binding to the IL-2 binding site of the IL-2receptor has been performed (see FIG. 19). Moreover, the crystalstructure of the ligand binding domain of IL-2 is known (see Qu, A andLeahy, DJ, Proc. Natl. Acad. Sci. USA 1995, 92: 10277-10281, which isexpressly incorporated by reference in its entirety). Moreover,favorable interactions between P3028 and at least one immunoregulatorypeptide inhibitor can facilitate the selection of additional amino acidresidues, D amino acid residues, and/or non-natural amino acid residuesto maintain favorable interactions.

In some embodiments, at least some of these immunoregulatory peptideinhibitors include D amino acids positions that are selected usingrational design or P3028 sequence/structure inhibitors. As noted in U.S.Pat. No. 7,957,912, rational design of peptides can start with a proteinbackbone structure and designs the amino acid sequence to modify theprotein's properties, while maintaining its three dimensional foldingproperties. In some embodiments, large numbers of sequences can bemanipulated using computer modeling, allowing for the design of proteinstructures (sequences, subsequences, etc.). Aspects of rational designare described in a number of publications, including, e.g., Malakauskasand Mayo (1998) “Design, Structure and Stability of a HyperthermophilicProtein Variant” Nature Struc. Biol. 5:470; Dahiyat and Mayo (1997) “DeNovo Protein Design: Fully Automated Sequence Selection” Science, 278,82-87. DeGrado, (1997) “Proteins from Scratch” Science, 278:80-81;Dahiyat, Sarisky and Mayo (1997) “De Novo Protein Design: Towards FullyAutomated Sequence Selection” J. Mol. Biol. 273:789-796; Dahiyat andMayo (1997) “Probing the Role of Pachng Specificity in Protein Design”Proc. Natl. Acad. Sci. USA, 94:10172-10177; Hellinga (1997) “RationalProtein Design—Combining Theory and Experiment” Proc. Natl. Acad. Sci.USA, 94: 10015-10017; Su and Mayo (1997 j “Coupling Backbone Flexibilityand Amino Acid Sequence Selection in Protein Design” Prot. Sci.6:1701-1707; Dahiyat, Gordon and Mayo (1997) “Automated Design of theSurface Positions of Protein Helices” Prot. Sci., 6:1333-1337; Dahiyatand Mayo (1996) “Protein Design Automation” Prot. Sci., 5:895-903.

In some embodiments, a library of variant of immunoregulatory peptideinhibitors of the P3028 sequence/structure containing one or more Damino acids and/or non-natural amino acids is screened for binding tothe P3028 sequence/structure. In some embodiments, the library isscreened for binding to P3028 (see Examples 10 and 12). In someembodiments, the library is screened for inhibiting binding of the P3028sequence/structure to the LFA-1 receptor (see Example 15).

In some embodiments, a lead molecule is used as a template for directeddrug design. A lead peptide, for example, can include, but is notlimited to one or more of the exemplary immunoregulatory peptideinhibitors that bind to the P3028 sequence/structure provided herein,such as in Example 12, (e.g., any one or more of the immunoregulatorypeptide inhibitors provided by SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68,76, 94-96, 98, 264-393, 583-586, or 589 or any one or more of thepeptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13). The lead peptide can be synthesized to include at least one Damino acid and/or at least one non-natural amino acid. In someembodiments, the binding activity of the first generation artificialimmunoregulatory peptide inhibitor is then detected, for example byevaluating the binding affinity for the P3028 sequence/structure, asdescribed herein. Additionally, the immunostimulatory activity of thefirst generation artificial immunoregulatory peptide inhibitor can bedetected, for example by evaluating the stimulation of an LFA-1 and/orIL-2 dependent response in a cell having a LFA-1 receptor or IL-2receptor, which can be inhibited by the P3028 sequence/structure. Oncethe binding and/or immunostimulatory activity of the first generationartificial immunoregulatory peptide inhibitor is obtained, at least oneadditional modification is made to the lead peptide and this secondgeneration immunoregulatory peptide inhibitor is evaluated for bindingto the P3028 sequence/structure and immunostimulatory activity. Theadditional modification can include, but is not limited to the additionor substitution, of at least one additional D amino acid and/or anon-natural amino acid. By iteratively conducting this screening andmodification procedure, more immunoregulatory peptide inhibitors can bemade.

Additionally, any one or more of the immunoregulatory peptide inhibitorsdescribed herein (e.g., any one or more of the immunoregulatory peptideinhibitors provided by SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96, 98, 264-393, 583-586, or 589 or any one or more of the peptidesprovided in Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13 cancomprise an N-terminal acetyl group and/or a C-terminal amide group.Furthermore, any one or more of the immunoregulatory peptide inhibitorsdescribed herein that comprise at least one D amino acid and/or at leastone non-natural amino acid (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 can be prepared to comprise an N-terminal acetylgroup and/or a C-terminal amide group).

Peptidomimetics

Some embodiments include compositions that comprise, consist of, orconsist essentially of peptidomimetic-based immunoregulatory peptideinhibitors. Peptidomimetics can include, but are not limited tosmall-molecule compounds having at least one biochemical interactionthat a peptide also has. Some peptidomimetics can include a smallmolecule backbone. Some peptidomimetics can include at least one R groupof a naturally-occurring amino acid covalently bonded to a smallmolecule backbone. Some peptidomimetics are substituted into at leastone position of a known peptide sequence. Accordingly, some embodimentsinclude a composition that comprises, consists of, or consistsessentially of one or more of the exemplary immunoregulatory peptideinhibitors that bind to the P3028 sequence/structure provided herein(e.g., any one or more of the immunoregulatory peptide inhibitorsprovided by SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98,264-393, 583-586, or 589 or any one or more of the peptides provided inTable 5.1, 5.4, 5.5, 5.6, or any variation or combination of variationsof P28R or P28 core as provided in Tables 5.3 and 13), wherein saidimmunoregulatory peptide inhibitor comprises at least one peptidomimeticsubstitution (e.g., a non-peptide bond, a small molecule backbone, or anartificial peptide linkage).

Some embodiments include a composition that comprises, consists of, orconsists essentially of one or more of the exemplary isolatedimmunoregulatory peptide inhibitors that bind to the P3028sequence/structure provided herein (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13, wherein said immunoregulatory inhibitors comprisea peptidomimetic substitution, which includes two or more monomers,wherein each monomer comprises a small molecule backbone covalentlybound to at least one R group. More embodiments, include a compositionthat comprises, consists of, or consists essentially of one or more ofthe exemplary immunoregulatory peptide inhibitors that bind to the P3028sequence/structure provided herein (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13, wherein said immunoregulatory inhibitors compriseat least one peptidomimetic small molecule backbone, wherein eachbackbone molecule includes one of an aryl group, for example a benzene,pyrrole, furan, thiophene, imidazole, oxazole, thiazole, triazole,pyrazole, pyridine, pyrazine, pyridazine and pyrimidine, and the like; acycloalkane or heterocycloalkane; a cycloalkene or heterocycloalkene; ora combination of two or more of the listed molecules. Each R group canbe the R group of a naturally occurring amino acid, or optionally can bea synthetic molecule. Each R group can be different, but two or more Rgroups can be the same. Some peptidomimetics include a first monomerthat binds to a first position of P3028, for example, and a secondmonomer that binds to a second position of P3028, in which the first andsecond monomers are covalently bonded (see, for example, the approach ofChen et al., ACS Chemical Biology 2009; 4(9): 769-81, hereby expresslyincorporated by reference in its entirety). The peptidomimetic backbonethat is incorporated into one or more of the exemplary immunoregulatorypeptide inhibitors that bind to the P3028 sequence/structure providedherein (e.g., any one or more of the immunoregulatory peptide inhibitorsprovided by SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98,264-393, 583-586, or 589 or any one or more of the peptides provided inTable 5.1, 5.4, 5.5, 5.6, or any variation or combination of variationsof P28R or P28 core as provided in Tables 5.3 and 13, can include aderivative of a β-turn peptidomimetic cyclic compound of formula (IV),as taught by U.S. Pat. No. 6,881,719, hereby expressly incorporated byreference in its entirety:

In some embodiments, R1 and R3 of the above Formula (IV) include Rgroups of natural and/or synthetic amino acids. Some embodiments includea composition that comprises, consists of, or consists essentially ofone or more of the exemplary immunoregulatory peptide inhibitors thatbind to the P3028 sequence/structure provided herein (e.g., any one ormore of the immunoregulatory peptide inhibitors provided by SEQ ID NOs:1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 orany one or more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, orany variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13), wherein said immunoregulatory inhibitorscomprise a peptidomimetic substitution that includes a polymer of two ormore derivatives of Formula (IV). In some embodiments, individualpeptidomimetic monomers or dimers derived from Formula (IV) are selectedfor their ability to bind the P3028 sequence/structure, and are thenassembled into polymers, thus producing a peptidomimetic polymer thatspecifically binds the P3028 sequence/structure.

As described in U.S. Pat. No. 7,816,324, peptidomimetics of eitherFormula (V) or Formula (VI) can be modified to mimic alpha-helix motifsthat bind to peptides.

Accordingly, aspects of the invention include a composition thatcomprises, consists of, or consists essentially of one or more of theexemplary immunoregulatory peptide inhibitors that bind to the P3028sequence/structure provided herein (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13), wherein said immunoregulatory inhibitors comprisea peptidomimetic substitution that incorporates the scaffold of formulaV or formula VI, which provide a rigid structure and places and orientssubstituents as an alpha-helix does. Substitution on the rigidtris-benzamide, for instance, can allow placement of three functionalgroups (R₁-R₃) corresponding to the side chains of amino acids found atthe i, i+4, and i+7 positions of an ideal alpha-helix, bound by thepeptide. As shown in FIG. 19, P3028 is modeled to bind to alphahelix-containing regions of the IL-2 receptor. Thus, some embodimentsinclude a composition that comprises, consists of, or consistsessentially of one or more of the exemplary immunoregulatory peptideinhibitors that bind to P3028 provided herein (e.g., any one or more ofthe immunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33,34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any oneor more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13), wherein said immunoregulatory inhibitors comprisea peptidomimetic substitution that incorporates a peptidomimetic offormula V or formula VI, wherein R₁-R₃ are selected from positions on aknown binding partner of P3028, for example the alpha subunit of theIL-2 receptor (CD25) (SEQ ID NO: 247), the LFA-1 receptor (CD11a—SEQ IDNO: 248 and CD18—SEQ ID NO: 249), or a peptide of SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13.

Embodiments also include a library of peptidomimetics. In someembodiments, the library of peptidomimetics is selected and/orsynthesized using a rational design approach. As disclosed in U.S. Pat.No. 7,816,324, hereby expressly incorporated by reference in itsentirety, a peptidomimetic library can be developed based on based on astructural knowledge of the interface of protein complexes. Thus, insome embodiments, peptidomimetic compounds are based on the structure ofP3028, and its interactions with known binding partners, for example theIL-2 receptor for which the crystal structure is known (see FIG. 19),the LFA-1 receptor, for which the crystal structure is known, the KKL15peptide (see Example 11), and known inhibitors of the P3028sequence/structure (e.g., SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96, 98, or 264-393 or any one or more of the peptides provided inTable 5.1). In some embodiments, alpha.-helix mimetics may be used tomodulate protein-protein or protein-peptide interaction. Thus, syntheticscaffolds that mimic key elements found in the interface between theP3028 sequence/structure and its binding partners is contemplated forthe development of small molecule immunoregulatory protein inhibitors.In some embodiments, the molecules of the peptidomimetic library areattached to a support, chip, surface, or substrate, for example amicroarray, as in U.S. Pat. No. 7,153,68, hereby expressly incorporatedby reference in its entirety. The section below provides more details onaptamer-based immunoregulatory peptide inhibitors.

Cyclic Peptides

Some embodiments include at least one cyclic peptide immunoregulatorypeptide inhibitor. Cyclic peptides, sometimes referred to as “loopedpeptides” are known in the art, and can be chemically synthesized (see,e.g., U.S. Pat. No. 7,589,170, hereby expressly incorporated byreference in its entirety herein), or synthesized in vivo (see, e.g.,U.S. Pat. No. 7,252,952, hereby expressly incorporated by reference inits entirety herein). As taught in U.S. Pat. No. 7,589,170, cyclisationcan be accomplished, for example by disulfide bond formation between twoside chain functional groups, amide or ester bond formation between oneside chain functional group and the backbone alpha-amino or carboxylfunction, amide or ester bond formation between two side chainfunctional groups, amide bond formation between the backbone alpha-aminoand carboxyl functions, or via a linker connecting two or more positionsof the peptide.

A portion of a peptide can be cyclized, or optionally, the entirepeptide can be cyclized, thereby forming a cyclic peptide. Thus, in someembodiments, the N terminus of the peptide is bonded to the C terminusof the peptide, thereby cyclizing the entire peptide. In someembodiments, the N terminus is bonded to the C terminus via analpha-amide linkage. In some embodiments, the N terminus is bonded tothe C terminus via a non-alpha-amide linkage, for example a bond betweenthe side chain of a Ser (S) or Thr(T) and the C-terminal carboxyl group,a disulfide bond between two Cys (C) residues, or a thioether between aTrp (W) and Cys (C) residue, or a synthetic linker molecule. In someembodiments, the C terminus is bonded to an internal amino acid via anon-alpha-amide linkage, for example, a bond between the side chain of aSer (S) or Thr(T) and the C-terminal carboxyl group, or a syntheticlinker molecule. In some embodiments, the N terminus or the C terminusis bonded to an internal amino acid, or two internal amino acids arebonded to each other via a non-alpha-amide linkage, for example adisulfide bond between two Cys (C) residues, or a thioether between aTrp (W) and Cys (C) residue.

In some embodiments, a cyclic peptide immunoregulatory peptide inhibitorincludes a single cyclic polypeptide structure. In some embodiments, acyclic peptide immunoregulatory peptide inhibitor includes two or morecyclic polypeptide structures, for example 2, 3, 4, 5, 6, 7, 8, 9, 10,11, or 12 cyclic polypeptide structures. Each cyclic polypeptidestructure can include at least two amino acid residues, for example,about 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 25, 26, 27, 28, 29, 30, 35, or 40 amino acid residues or a rangethat is defined by any two of these numbers.

In some embodiments, a library of cyclic peptides is screened for cyclicpeptides that bind to albumin-derived immunoregulatory peptides, forexample, the peptides of Tables 1-4 or 5.4 (SEQ ID NOs: 183-184,188-246). Screening of cyclic peptides libraries is described in PCTPublication WO 95/09344, hereby incorporated by reference in itsentirety. In some embodiments, a library of cyclic peptides issynthesized. In some embodiments, each looped peptide in the library hasthe same length, for example 5-meres, 6-meres, 7-meres, 8-meres,9-meres, 10-meres, 11-meres, or 12-meres. In some embodiments, thelibrary includes cyclic peptides of two or more lengths. As shown inExample 12, a library of 6-meres was synthesized and was screened forpeptides that bind to P3038. Positional scans (i.e., single amino acidsubstitutions at each position) of a lead cyclic peptide (SEQ ID NO:265) identified as exhibiting appreciable binding to P3028 wereperformed to identify additional cyclic 6-meres that bind to P3028. Itwas observed that the two 6-meres that bound to P3028 with the highestaffinity (SEQ ID NOs: 266-267) had homology to linear peptides that bindto P3028 (see FIG. 32). Thus, it is contemplated herein that aspects oflinear peptides that bind to albumin-derived immunoregulatory peptidescan be incorporated into cyclic peptides, thus producing cyclic peptidesthat bind albumin-derived immunoregulatory peptides.

In some embodiments, inhibitors of albumin-derived immunoregulatorypeptides or structures, or a portion thereof is cyclized. In someembodiments, a peptide of any of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68,76, 94-96, 98, 264-393, 583-586, or 589 or any one or more of thepeptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13, or a portion thereof is modified to facilitate cyclization. Insome embodiments, amino residues containing side chains that can forcyclic structures, for example Cysteine, are added to the N terminus, Cterminus, and/or internal positions of any of the peptide of SEQ ID NOs:1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 orany one or more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, orany variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13.

Aptamers

Aptamers are small molecules that specifically bind to a targetmolecule. Aptamers can include oligonucleotide aptamers, for exampleDNA, RNA, or synthetic oligonucleotides. In some embodiments,oligonucleotide aptamers include oligonucleotides with a syntheticbackbone, for example morpholinos. Aptamers can also include peptideaptamers. Aspects of the invention include a composition that comprises,consists of, or consists essentially of an aptamer (e.g., nucleic acidbased or peptide based), wherein said aptamer corresponds or mimics oneor more of the exemplary immunoregulatory peptide inhibitors that bindto the P3028 sequence/structure provided herein (e.g., any one or moreof the immunoregulatory peptide inhibitors provided by of SEQ ID NOs:1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 orany one or more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, orany variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13). Some embodiments of the inventioninclude aptamers that bind specifically to the P3028 sequence/structure.

Some embodiments include a library of oligonucleotide aptamers.Oligonucleotide aptamers that bind to the P3028 sequence/structure canbe readily developed given the teachings described herein. As describedin U.S. Pat. No. 7,745,607, which is hereby expressly incorporated byreference in its entirety herein, an aptamer that binds specifically toa target, for example the P3028 sequence/structure can be identified byinteracting an antisense oligonucleotide with a library oligonucleotidehaving a complementary antisense binding domain to form a doublestranded duplex, said library oligonucleotide further having a randomnucleotide domain; ii) immobilizing the duplex structure on a solidsupport; iii) incubating the duplex structure in the presence of theP3028 sequence/structure; and iv) collecting library oligonucleotidesthat dissociate from the duplex structure and bind to the P3028sequence/structure. Alternatively, a library of oligonucleotides can beprovided in which the library oligonucleotide is hybridized to abiotinylated antisense oligonucleotide to form a duplex molecule. Theduplex molecules are immobilized on a surface, for example avidin-coatedbeads. A target, such as P3028 is provided and contacted with theoligonucleotides. Oligonucleotides which have bound to the target, arecollected and amplified. Similar screening approaches can be used toidentify peptide-based aptamers that bind to the P3028sequence/structure. Peptide based aptamers that bind to the P3028sequence/structure, can mimic the immunoregulatory peptide inhibitorsdescribed herein (e.g., any one or more of SEQ ID NOs: 1-33, 34, 46-53,64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one or more ofthe peptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13), and variants thereof. The section below discusses many of themodifications that can be incorporated in an immunoregulatory peptideinhibitor described herein.

Modifications

Embodiments described herein also include a composition that comprises,consists of, or consists essentially of one or more of the exemplaryisolated immunoregulatory peptide inhibitors that bind to the P3028sequence/structure provided herein (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by (SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13), wherein said immunoregulatory inhibitors compriseat least one modification (e.g., glycosylation, nitrosylation, acytotoxin, a detectable moiety, or a radionuclide). Glycosylation caninclude the addition of polyethylene glycol (PEG). The addition of PEGcan increase the solubility of one or more of the immunoregulatorypeptide inhibitors described herein in aqueous solution, protect themolecule from attack by a host's immune system, and/or increase thehalf-life of the molecule in the host.

In some embodiments, the immunoregulatory peptide inhibitors aredirectly bound to a cytotoxin. In some embodiments, a peptide consistingof, consisting essentially of, or comprising one of SEQ ID NOs: 1-33,34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any oneor more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 is covalently bound to a cytotoxin. In someembodiments, the immunoregulatory peptide inhibitor is attached to thetoxin via a linker. In some embodiments, a peptide consisting of,consisting essentially of, or comprising one of SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 is attached to a cytotoxin via a linker. A widearray of linker technologies can be employed. Linkers can be cleavableor non-cleavable. It is known that in many cases, the full cytotoxicpotential of a drug can be observed when the cytotoxic molecules arereleased from a conjugates, for example an inhibitor of animmunoregulatory peptide, in unmodified form at the target site. One ofthe cleavable linkers that has been employed for the preparation ofcytotoxin conjugates is an acid-labile linker based on cis-aconitic acidthat takes advantage of the acidic environment of differentintracellular compartments such as the endosomes encountered duringreceptor mediated endocytosis and the lysosomes. Shen and Ryserintroduced this method for the preparation of conjugates of daunorubicinwith macromolecular carriers (Biochem. Biophys. Res. Commun.102:1048-1054 (1981)). Yang and Reisfeld used the same technique toconjugate daunorubicin to an anti-melanoma antibody (J. Natl. Canc.Inst. 80:1154-1159 (1988)). Recently, Dillman et al. also used anacid-labile linker in a similar fashion to prepare conjugates ofdaunorubicin with an anti-T cell antibody (Cancer Res. 48:6097-6102(1988)). An alternative approach, explored by Trouet et al. involvedlinking daunorubicin to a targeting molecule via a peptide spacer arm(Proc. Natl. Acad. Sci. 79:626-629 (1982)). This was done under thepremise that free drug could be released from such a conjugate by theaction of lysosomal peptidases. One skilled in the art will appreciatethat cleavable linker approaches employed for conjugating cytotoxins toantibodies can also be employed to conjugate a peptide, for example oneof SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393,583-586, or 589 or any one or more of the peptides provided in Table5.1, 5.4, 5.5, 5.6, or any variation or combination of variations ofP28R or P28 core as provided in Tables 5.3 and 13 to a cytotoxin.

Exemplary cytotoxins that can be incorporated into one or more of theexemplary immunoregulatory peptide inhibitors that bind to the P3028sequence/structure provided herein (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13) include: radiotoxins, monomethylauristatin-E,monomethylauristatin-F, aplidin, azaribine, anastrozole, azacytidine,bleomycin, bortezomib, bryostatin-1, busulfan, calicheamycin,camptothecin, 10-hydroxycamptothecin, carmustine, celebrex,chlorambucil, cisplatin, irinotecan (CPT-11), SN-38, carboplatin,cladribine, cyclophosphamide, cytarabine, dacarbazine, docetaxel,dactinomycin, daunomycin glucuronide, daunorubicin, dexamethasone,diethylstilbestrol, doxorubicin, doxorubicin glucuronide, epirubicinglucuronide, ethinyl estradiol, estramustine, etoposide, etoposideglucuronide, etoposide phosphate, floxuridine (FUdR),3′,5′-O-dioleoyl-FudR (FUdR-dO), fludarabine, flutamide, fluorouracil,fluoxymesterone, gemcitabine, hydroxyprogesterone caproate, hydroxyurea,idarubicin, ifosfamide, L-asparaginase, leucovorin, lomustine,mechlorethamine, medroprogesterone acetate, megestrol acetate,melphalan, mercaptopurine, 6-mercaptopurine, methotrexate, mitoxantrone,mithramycin, mitomycin, mitotane, phenyl butyrate, prednisone,procarbazine, paclitaxel, pentostatin, PSI-341, saporin, semustinestreptozocin, tamoxifen, taxanes, testosterone propionate, thalidomide,thioguanine, thiotepa, teniposide, topotecan, uracil mustard, velcade,vinblastine, vinorelbine, vincristine, ricin, for example ricin A chain,abrin, ribonuclease, onconase, rapLR1, DNase I, Staphylococcalenterotoxin-A, pokeweed antiviral protein, gelonin, diphtheria toxin,Pseudomonas exotoxin, and Pseudomonas endotoxin.

Exemplary detectable moieties (which may also be referred to herein as“detectable labels” that can be incorporated into one or more of theexemplary immunoregulatory peptide inhibitors that bind to the P3028sequence/structure provided herein (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13) or to an antibody that binds specifically to P3028include: a radiolabel, a fluorophore, biotin, a fluorescent protein,colloidal gold, and/or a coenzyme. Radiolabels can include ³H and ¹⁴C.Fluorophores can include Alexa-Fluor dyes, Pacific Blue, Pacific Orange,Cascade Blue, Cascade Yellow and R-phycoerythrin, fluorescein (FITC),rhodamine, Texas red, BODIPY family dyes, Cy2, Cy3, C5, and Cy7.Fluorescent proteins can include Blue, Cyan, Green, Yellow, and Redfluorescent proteins. In some embodiments, fluorescent labels include aFRET pair. For example, a single peptide can be attached to a FRET donorand FRET acceptor, which are configured so that the FRET acceptor issubstantially within a FRET radius of the FRET donor when the peptide isin a first configuration (for example, bound to target), but not whenthe peptide is in a second configuration (for example, unbound totarget). For example, a first peptide can be attached to a FRETacceptor, and a second peptide can be attached to a FRET donor, so thatthe FRET acceptor is substantially within a FRET radius of the FRETdonor when the first peptide and second peptide are each bound to atarget, for example a target cell, but not when at least one peptide isunbound to the target. In some embodiments, fluorescent label includes afluorophore and a quencher. The fluorophore and quencher can each beattached to the peptide so that the quench absorbs electromagneticradiation emitted by the fluorophore when the peptide is in a firstconfiguration (for example, bound to target), but not when the peptideis in a second configuration (for example, unbound to target). Coenzymescan include vitamins such as biotin.

Exemplary radionuclides that can be incorporated into one or more of theexemplary immunoregulatory peptide inhibitors that bind to the P3028sequence/structure provided herein (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13) or an antibody that binds specifically to P3028include: ¹¹¹I, ¹³¹I, ⁹⁰Y, ⁶⁷Cu, ¹⁸⁶Re, ¹⁸⁸Re, ²¹²Bi or ²¹¹At. Preferableradiolabeled immunoregulatory peptide inhibitors are able to delivermore than 6000 rads to a tumor, for example, and have sufficientaffinity so that the patient's bone marrow is not exposed to more than300 rads. The section that follows describes in greater detail some ofthe embodiments, which encompass protein complexes comprising animmunoregulatory peptide inhibitor described herein.

In some embodiments, a diagnostic kit is provided. The kit can includeany one or more of the immunoregulatory peptide inhibitors provided bySEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586,or 589 or any one or more of the peptides provided in Table 5.1, 5.4,5.5, 5.6, or any variation or combination of variations of P28R or P28core as provided in Tables 5.3 and 13 or an antibody that bindsspecifically to any of the peptides of SEQ ID NOs: 183-185 or 188-246,for example P3028 (SEQ ID NO: 185). The kit can also include adetectable moiety as described herein. In some embodiments, the peptideinhibitor or antibody of the kit is biotinylated.

Carrier Molecules

Some embodiments include a carrier molecule. Carrier molecules, can forexample, increase the stability or half-life, increase the solubility,increase the absorption, target the peptide to an appropriate cell,organ or tissue, and/or minimize an immune response against atherapeutic molecule.

Exemplary carrier molecules include human serum albumin; a polymerhaving a plurality of acid moieties (see PCT Pub. No. WO 01/93911);anionic group-containing amphiphilic block copolymers that, when used asa drug carrier for a cationic therapeutic molecule can improve stabilityof that molecule (see PCT Pub. No. WO 03/00778); cyclodextrin and acidsfor improving the properties of basic therapeutic molecules (EuropeanPat. No. 0 681 481); lipids as carriers for hydrophobic therapeuticmolecules (see PCT Pub. No. WO 04/064731); immunoglobulins; and Fcfragments as carriers for improving half-life and minimizing immuneresponse (see U.S. Pat. No. 7,736,653). In some embodiments, animmunoregulatory peptide inhibitor (e.g., a peptide comprising,consisting of, or consisting essentially of SEQ ID NOs: 1-33, 34, 46-53,64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one or more ofthe peptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13) includes or is joined to a carrier. In some embodiments, animmunoregulatory peptide inhibitor (e.g. a peptide comprising,consisting of, or consisting essentially of SEQ ID NOs: 1-33, 34, 46-53,64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one or more ofthe peptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13) includes two or more carriers.

In some embodiments, an immunoregulatory peptide inhibitor is providedwith a degradable particle. Without being limited by any theory, it iscontemplated that a degradable particle can permit an immunoregulatoryparticle to be soluble and exert its activity for a controlled period oftime in the systemic circulation. Accordingly, in some embodiments, adegradable particle comprising an immunoregulatory peptide inhibitor(for example, a peptide comprising, consisting of, or consistingessentially of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98,264-393, 583-586, or 589 or any one or more of the peptides provided inTable 5.1, 5.4, 5.5, 5.6, or any variation or combination of variationsof P28R or P28 core as provided in Tables 5.3 and 13) is provided. Insome embodiments the degradable particle comprising the immunoregulatorypeptide inhibitor is administered to a subject in need. Optionally, thedegradable particle can be administered systemically. Optionally, thedegradable particle can be administered locally, for example at or neara site of immunosuppression (e.g. within 10 cm, 9 cm, 8 cm 7 cm, 6c, 5cm, 4 cm, 3 cm, 2 cm, 1 cm, or 0.5 cm of the site of immunosuppressionor a range defined by any two of these numbers). In some embodiments,the subject suffers from LFA-1 receptor blockage by an immunoregulatorypeptide sequence of any of Tables 1-4. Optionally, the degradableparticle can be coadministered with one or more additional therapeuticagents. For example, if a the immunoregulatory peptide inhibitor isuseful for de-blocking an LFA-1 receptor (e.g. displaces boundimmunoregulatory peptides or 3028 structures from the LFA-1 receptor), atherapeutic agent that stimulates an immune response, for example via anLFA-1 receptor can be useful for co-administering with theimmunoregulatory peptide inhibitor and degradable particle. In someembodiments, the additional therapeutic agent is administered at thesame time as the immunoregulatory peptide inhibitor, for example as partof the degradable particle. In some embodiments, the additionaltherapeutic agent is administered after the immunoregulatory peptideinhibitor, for example at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 hours afterwards, orabout 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, or 31 days afterwards or arange defined by any two of aforementioned times. A variety of suitabledegradable particles can be used in accordance with embodiments herein.In some embodiments, the degradable particle comprises a sphere, forexample a microsphere. In some embodiments, the degradable particlecomprises a nanoparticle. In some embodiments, the degradable particlecomprises a starch or sugar. In some embodiments, the degradableparticle comprises an organic polymer or a combination of organicpolymers, for example, polyesters, polyphosphate esters,polyphosphazenes, polyorthoesters, polyanhydrides, polycarbonates,polyamides, poly-lactic acid, a poly-glycoloyic acid, or a combinationof two or more polymers, for example two or more of the listed polymers.

Protein Complexes

Some embodiments include a composition comprising an isolated proteincomplex that comprises an immunoregulatory peptide inhibitor. Theisolated protein complex can include an immunoregulatory peptide, forexample P3028 (SEQ ID NO: 185) or any one or more of theimmunoregulatory peptides described in Tables 1-4 (SEQ ID NOs: 183-184and 188-246) and at least one immunoregulatory peptide inhibitor (e.g.,any one or more of the peptides provided in Table 5.1). In someembodiments, the isolated protein complex includes peptide 3028 (SEQ IDNO: 185) and an inhibitor peptide that includes the sequence of SEQ IDNOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96 or 98 or any one or more ofthe peptides provided in Table 5.1. Exemplary protein complexes thatinclude each of the peptides SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96, 98, 264-393, 583-586, or 589 or any one or more of the peptidesprovided in Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13 bound tothe P3028 sequence/structure are provided in Examples 10, 11 and 12 andTable 5.1. The protein complex can include at least one favorableelectrostatic interaction between an amino acid residue of P3028 or avariant thereof, and an amino acid of an inhibitor peptide or peptidemimetic. The protein complex can include at least one favorablehydrophobic interaction between an amino acid residue of P3028 or avariant thereof, and an amino acid of an inhibitor peptide or peptidemimetic (see Example 11). In some embodiments, the protein complexincludes a variant of P3028 having at least about 80% identity to P3028,for example greater than or equal to about 80%, 81%, 82%, 83%, 84%, 85%,86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity to P3028. The protein complex can further include at least oneprotein bound to a cancer cell, for example a surface protein. Thus, insome embodiments, the isolated protein complex can localize to thesurface of a cancer cell.

Accordingly, some embodiments include a method of making a proteincomplex that comprises one or more of the immunoregulatory peptideinhibitors described herein. The methods can be practiced, for example,by binding an immunoregulatory peptide inhibitor, as described herein toP3028, or a variant or fragment thereof. The method can optionallyinclude detecting the presence of the complex, which can be accomplishedby rampo studies, as described herein.

Some embodiments include methods of binding a peptide comprising,consisting or, or consisting essentially of SEQ ID NOs: 1-33, 34, 46-53,64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one or more ofthe peptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13 to a molecule that comprises the P3028 sequence/structure (SEQ IDNO: 185). Some embodiments include methods of binding a peptidecomprising, consisting of, or consisting essentially of at least one ofSEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586,or 589 or any one or more of the peptides provided in Table 5.1, 5.4,5.5, 5.6, or any variation or combination of variations of P28R or P28core as provided in Tables 5.3 and 13 to a molecule comprising a variantof the P3028 sequence/structure (SEQ ID NO: 185). Some embodimentsinclude methods of binding a peptide including at least one of SEQ IDNOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589or any one or more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6,or any variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13 to a protein that comprises the P3028sequence/structure or a fragment of P3028 (SEQ ID NO: 185), wherein thefragment of P3028 has a length of at least about 10 amino acids, morepreferably 11 amino acids, more preferable 12 amino acids, morepreferably 13 amino acids, more preferably 14 amino acids, morepreferably 15 amino acids, more preferably 16 amino acids, or morepreferably 17 amino acids. In some embodiments, the binding includesfavorable hydrophilic and/or electrostatic interactions between membersof the protein complex. In some embodiments, the binding includescovalent bonds between members of the protein complex, for examplethrough crosslinking. Crosslinking can be induced chemically, and/or viaelectromagnetic radiation, for example electromagnetic radiation in theultraviolet spectrum.

In some embodiments, the peptide comprises at least one of SEQ ID NOs:1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13. Exemplary supports include a pin, bead, surface,matrix, artificial cell surface, or cell surface. For example, thepeptide can be affixed via an affinity tag to a support. In someembodiments, P3028, or a variant or fragment thereof is affixed to asupport. In some embodiments, the peptide including at least one of SEQID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 583-586, or 589 orany one or more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, orany variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13 is affixed to a support, and P3028 or avariant or fragment thereof is dissolved in a solvent. In someembodiments, the peptide including at least one of SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 583-586, or 589 or any one or more ofthe peptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13 is dissolved in a solvent, and P3028, or a variant or fragmentthereof is affixed to a support. In some embodiments, the peptideincluding at least one of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96, 98, 583-586, or 589 or any one or more of the peptides providedin Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13 andP3028 are each dissolved in a solvent, for example serum.

In some embodiments, the binding occurs in an organism, for example inextracellular matrix, and/or serum or in a biological sample obtainedfrom an organism, such as a human. Biological samples can include atleast one cell, tissue, or extracellular composition of an organism,include extracts, purified extracts, and/or fractions thereof. Exemplarybiological samples include whole blood, serum, bone marrow, isolatedimmune cells, and tumor biopsies. Isolated immune cells can includeleukocytes, and peripheral blood mononuclear cells (PBMC's), for examplelymphocytes, monocytes, or macrophages. The method can includedelivering at least one member of the complex, for example a peptideincluding at least one of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96, 98, 583-586, or 589 or any one or more of the peptides providedin Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13, to theorganism. In some embodiments, the binding occurs in vitro, for examplein a buffer solution or in a biological sample. The method can includeadding at least one member of the complex, for example a peptideincluding at least one of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96, 98, 583-586, or 589 or any one or more of the peptides providedin Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13, to asolution that contains the remaining members of the complex.Alternatively, the method can include adding two or more members of thecomplex to a solution for example a peptide including at least one ofSEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 583-586, or 589or any one or more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6,or any variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13 and P3028 or a fragment or variantthereof. In some embodiments, a peptide including at least one of SEQ IDNOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 583-586, or 589 or anyone or more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 is added to a biological sample.

Some embodiments include detecting the presence of the complex. Someembodiments include detecting the presence of the P3028sequence/structure bound to a peptide that is affixed to a support (seeExample 12), for example by ELISA. Some embodiments include detectingthe presence of a complex by FRET. For example a FRET donor fluorophorecan be attached to a first member of the complex, and a FRET acceptorfluorophore can be attached to a second member of the complex, so thatFRET transfer occurs only when the complex is formed. Some embodimentsinclude detecting the presence of a complex by cessation of quenching.For example a member of the complex can be attached to a fluorophore anda quencher for electromagnetic radiation emitted by the fluorophore, sothat when the complex member is unbound, the fluorophore issubstantially within the quencher radius, and the quencher absorbselectromagnetic radiation emitted by the fluorophore (e.g., a quenchercan be attached to the N terminal and a fluorophore attached to the Cterminal, or a quencher can be attached to the C terminal, and afluorophore attached to the N terminal). Upon complex formation, thefluorophore can be outside of the quencher radius, thus permittingdetection of electromagnetic radiation emitted by the fluorophore.

Some embodiments include detecting the presence of the complex bydetecting of complex function. For example, an immune cell in whichpeptide 3028 is bound to the LFA-1 and/or IL-2 receptor can exhibitreduced IL-2-induced proliferation, T cell receptor stimulation,leukocyte spreading, immune cell migration, and/or NK cell cytotoxicity(see Examples 2-6). Direct or indirect detection of increasedIL-2-induced proliferation, T cell receptor stimulation, leukocytespreading, immune cell migration, and/or NK cell cytotoxicity, forexample increase in comparison to an untreated control sample in whichat least one member of the complex was not added, can detect complexformation. For example, as shown in Example 13, the formation of acomplex between the P3028 sequence/structure and an immunoregulatorypeptide inhibitor can increase lymphocyte stimulation. For example, asshown in Example 1, the formation of a complex can unblock theLFA-1receptor. Thus, some embodiments include detecting complex formationindirectly by, for example, detecting increased lymphocyte stimulation,detecting unblocked LFA-1 receptor, and/or detecting immune cellstimulation via an unblock LFA-1 receptor, as compared to a controlsample that is known to lack complex formation.

Some embodiments include detecting the presence of the complex bydetecting localization of complex members. In some embodiments,detecting the presence of the complex includes detecting the presence ofan immunoregulatory peptide inhibitor including at least one of SEQ IDNOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589or any one or more of the peptides provided in Table 5.1, 5.4, 5.5, 5.6,or any variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13, or a peptidomimetic that bindsspecifically to the P3028 sequence/structure on tumor cells. As shown inExample 1, the P3028 sequence/structure can bind to tumor cells. Asshown in Example 14, an inhibitor of the P3028 sequence/structure canbind to tumor cells, for example by binding to the P3028sequence/structure. Thus, in some embodiments, the presence of aninhibitor of the P3028 sequence/structure, for example, at least one ofSEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586,or 589 or any one or more of the peptides provided in Table 5.1, 5.4,5.5, 5.6, or any variation or combination of variations of P28R or P28core as provided in Tables 5.3 and 13 on a tumor cell can indicatecomplex formation. Thus, complex formation can be detected bycolocalization of an inhibitor with at least one marker of a tumor cell.Colocalization can be detected, for example by immunohistochemistry orflow cytometry. In some embodiments, the inhibitor is labeled, forexample with a fluorophore or radiolabel. In some embodiments, theinhibitor is detected, for example with a primary antibody thatspecifically binds to the inhibitor. The section that follows describesin greater detail some of the nucleic acid embodiments, which encode animmunoregulatory peptide inhibitor.

Nucleic Acids Encoding Inhibitor Peptides

Some embodiments include isolated nucleic acids encoding animmunoregulatory peptide inhibitor. One skilled in the art willappreciate that for a given peptide sequence, a nucleic acid sequenceencoding that peptide sequence can readily be determined, and due to thedegeneracy of the genetic code, more than one nucleic acid sequence canencode any one peptide. A nucleic acid sequence encoding a peptide canbe incorporated into an expression vector using known techniques, aswell. Expression vectors can be used to produce the peptide in anexpression system, for example a host cell, a host organism, a cell-freeexpression system, and the like. Expression vectors can also be used toproduce a peptide in an organism, for example a patient in need ofblocking of immunosuppression, as described herein. Exemplary expressionvectors include plasmid DNA, such as a pVAX construct, bacteriophageDNA, cosmid DNA, artificial chromosomes such as BACs and YACs,retrovirus systems, for example lentivirus, DNA virus systems, forexample adenovirus or vaccinia virus (e.g., MVA). For peptides that donot have an N-terminal amino acid that corresponds to a translationstart codon (typically Met corresponding to ATG), expression vectors caninclude an in-frame translation start codon. Such an amino acid can beseparated from the N-terminal of the peptide by a cleavable linker, forexample a peptide sequence that is cleaved by a protease. Expressionvectors can include transcriptional regulatory sequences, for examplecore promoters, transcriptional enhancers, and/or insulator sequences.Such sequences can facilitate the assembly of transcriptional machinery(for example RNA Polymerase III), and the subsequent production of atranscript encoding the peptide (for example, by facilitating aheterochromatic environment that is favorable to transcription).

In some embodiments, an expression vector encodes two or more copies ofa peptide, and/or two or more unique peptides. In some embodiments, anexpression vector encodes two or more peptides, and each peptide isunder the control of a unique transcription unit (e.g., promoter,transcriptional enhancers, and/or transcription terminator). In someembodiments, a nucleic acid encoding two or more peptides is under thecontrol of a single transcription unit. In such embodiments, a sequenceencoding an individual peptide can be under the control of an individualtranslation start site, for example an Internal Ribosome Entry Site(IRES). In such embodiments, a single nucleic acid can encode a proteinor polypeptide encoding two or more peptides, which are separated by atleast one protease target site.

One skilled in the art will appreciate that polynucleotides encodingpeptides, such as peptide inhibitors, can be readily constructed basedupon the sequence of the peptide. Exemplary polynucleotides encoding thesequences of immunoregulatory peptide inhibitor peptides of (SEQ ID NOs:2-33) are provided in Table 5.2. One skilled in the art will appreciatethat due to the degeneracy of the genetic code, a given polypeptide canbe encoded by more than one polynucleotide may encode. Thus, providedherein, for example in Table 5.2, are consensus polynucleotides thataccount for typical degeneracy of the genetic code, as well as exemplarypolynucleotides. The polynucleotides of Table 5.2 are provided by way ofexample, and include SEQ ID NOs: 102-165. On skilled in the art willfurther appreciate that additional polynucleotides can encode peptideinhibitors such as the peptide inhibitors disclosed herein (e.g.,polynucleotides encoding any one or more of the peptides provided inTable 5.1 are embodiments). For example, polynucleotides can be modifiedpost-transcriptionally, for example by alternative splicing, and/or byenzymes such as RNA-specific adenosine deaminase (ADAR) that can modifythe bases of polynucleotides.

TABLE 5.2 Polynucleotides encoding peptide inhibitors of the P3028sequence/structure Seq ID NO Description 102 Consensus polynucleotideencoding P28R (SEQ ID NO: 2) 103 Exemplary NT encoding P28R (SEQ ID NO:2) 104 Consensus polynucleotide encoding SEQ ID NO: 3 105 Exemplary NTencoding SEQ ID NO: 3 106 Consensus polynucleotide encoding SEQ ID NO: 4107 Exemplary NT encoding SEQ ID NO: 4 108 Consensus polynucleotideencoding SEQ ID NO: 5 109 Exemplary NT encoding SEQ ID NO: 5 110Consensus polynucleotide encoding SEQ ID NO: 6 111 Exemplary NT encodingSEQ ID NO: 6 112 Consensus polynucleotide encoding SEQ ID NO: 7 113Exemplary NT encoding SEQ ID NO: 7 114 Consensus polynucleotide encodingSEQ ID NO: 8 115 Exemplary NT encoding SEQ ID NO: 8 116 Consensuspolynucleotide encoding SEQ ID NO: 9 117 Exemplary NT encoding SEQ IDNO: 9 118 Consensus polynucleotide encoding SEQ ID NO: 10 119 ExemplaryNT encoding SEQ ID NO: 10 120 Consensus polynucleotide encoding SEQ IDNO: 11 121 Exemplary NT encoding SEQ ID NO: 11 122 Consensuspolynucleotide encoding SEQ ID NO: 12 123 Exemplary NT encoding SEQ IDNO: 12 124 Consensus polynucleotide encoding SEQ ID NO: 13 125 ExemplaryNT encoding SEQ ID NO: 13 126 Consensus polynucleotide encoding SEQ IDNO: 14 127 Exemplary NT encoding SEQ ID NO: 14 128 Consensuspolynucleotide encoding SEQ ID NO: 15 129 Exemplary NT encoding SEQ IDNO: 15 130 Consensus polynucleotide encoding SEQ ID NO: 16 131 ExemplaryNT encoding SEQ ID NO: 16 132 Consensus polynucleotide encoding SEQ IDNO: 17 133 Exemplary NT encoding SEQ ID NO: 17 134 Consensuspolynucleotide encoding SEQ ID NO: 18 135 Exemplary NT encoding SEQ IDNO: 18 136 Consensus polynucleotide encoding SEQ ID NO: 19 137 ExemplaryNT encoding SEQ ID NO: 19 138 Consensus polynucleotide encoding SEQ IDNO: 20 139 Exemplary NT encoding SEQ ID NO: 20 140 Consensuspolynucleotide encoding SEQ ID NO: 21 141 Exemplary NT encoding SEQ IDNO: 21 142 Consensus polynucleotide encoding SEQ ID NO: 22 143 ExemplaryNT encoding SEQ ID NO: 22 144 Consensus polynucleotide encoding SEQ IDNO: 23 145 Exemplary NT encoding SEQ ID NO: 23 146 Consensuspolynucleotide encoding SEQ ID NO: 24 147 Exemplary NT encoding SEQ IDNO: 24 148 Consensus polynucleotide encoding SEQ ID NO: 25 149 ExemplaryNT encoding SEQ ID NO: 25 150 Consensus polynucleotide encoding SEQ IDNO: 26 151 Exemplary NT encoding SEQ ID NO: 26 152 Consensuspolynucleotide encoding SEQ ID NO: 27 153 Exemplary NT encoding SEQ IDNO: 27 154 Consensus polynucleotide encoding SEQ ID NO: 28 155 ExemplaryNT encoding SEQ ID NO: 28 156 Consensus polynucleotide encoding SEQ IDNO: 29 157 Exemplary NT encoding SEQ ID NO: 29 158 Consensuspolynucleotide encoding SEQ ID NO: 30 159 Exemplary NT encoding SEQ IDNO: 30 160 Consensus polynucleotide encoding SEQ ID NO: 31 161 ExemplaryNT encoding SEQ ID NO: 31 162 Consensus polynucleotide encoding SEQ IDNO: 32 163 Exemplary NT encoding SEQ ID NO: 32 164 Consensuspolynucleotide encoding SEQ ID NO: 33 165 Exemplary NT encoding SEQ IDNO: 33

Accordingly, embodiments described herein also include a compositionthat comprises, consists of, or consists essentially of an isolatednucleic acid or polynucleotide that encodes one or more of the exemplaryimmunoregulatory peptide inhibitors that bind to the P3028sequence/structure provided herein (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96 or 98 or any one or more of the peptidesprovided in Table 5.1). Vectors, constructs, and plasmids comprising theaforementioned nucleic acids or polynucleotides are also embodiments.The following section discusses additional components that may beincluded in one or more of the compositions described herein.

Pharmaceutical Compositions

In some embodiments, a pharmaceutical composition comprising, consistingessentially of or consisting of a peptide inhibitor (e.g., any one ormore of the peptides provided in Table 5.1) is provided. Thepharmaceutical composition can include a peptide inhibitor as describedherein and a pharmaceutically acceptable ingredient as described herein.Exemplary pharmaceutically acceptable ingredients include diluents,carriers, excipients and/or buffers. In some embodiments, the peptideinhibitor comprises, consists of, or consists essentially of a peptideinhibitor as described herein. For example, a composition can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of the peptide ofFormula (I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166). In some embodiments, X is anoptional sequence, and can be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO:168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO:171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO:254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO:257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO:259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO:262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, orQ, or absent. In some embodiments, X₁ is one of FF, FM, FS, FV, FT, FL,AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, or VL. In some embodiments,X₂ is one of LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH. In someembodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT,LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT,VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST,MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN,QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN,VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN,MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP,QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP,VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ IDNO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR,QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR,VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR.In some embodiments, X₄ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, if X is absent, X₁ is FF, and X₂ is LS. Insome embodiments, the isolated peptides comprising Formula (I). have alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Additionally, a composition can comprise, consist of, or consistessentially of a peptide inhibitor that comprises, consists of, orconsists essentially of a peptide of Formula (II) X₂₀TFFVKLSX₂₁X₂₂, (SEQID NO: 173). In some embodiments, X₂₀ is an optional sequence, and canbe KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO: 176),KKED (SEQ ID NO: 177), KLD, LD, or D, or absent. X₂₁ is an optionalsequence, and can be LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT,QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT,VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT,MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN,QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN,VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN,LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP,QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP,VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO:815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR,QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR,VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR, orabsent. In some embodiments, X₂₂ is an optional sequence, and can be ER,or E, or absent. In some embodiments, the isolated peptides comprisingFormula (II) have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, a composition can comprise, consist of, or consistessentially of a peptide inhibitor that comprises, consists of, orconsists essentially of a peptide of Formula (III) X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄(SEQ ID NO: 178), or of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96 or 98. In some embodiments, X₃₁ is an optional sequence, and canbe F, S, M, V, T, or L, or absent. In some embodiments, X₃₁ is F. Insome embodiments, X₃₂ can be S, Q, M, T, or H. In some embodiments, X₃₂is S. X₃₃ can be F, M, Q, H, N, P, S, G, A, or R. In some embodiments,X₃₄ is F. X₃₄ is an optional sequence, and can be R, or absent. In someembodiments, X₃₀ is an optional sequence, and can be KKLDTF (SEQ ID NO:179), KLDTF (SEQ ID NO: 180), LDTF (SEQ ID NO: 181), DTF, TF, or F, orabsent. In some embodiments, the isolated peptides comprising Formula(III) have a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, a composition can comprise, consist of, or consistessentially of a peptide inhibitor that comprises, consists of, orconsists essentially of a peptide of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, a composition can comprise, consist of, or consistessentially of a peptide inhibitor that comprises, consists of, orconsists essentially of a peptide of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent, or absent. In some embodiments, X₈₀₂ is an optional sequence,and can be LSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ IDNO: 717), LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ IDNO: 720), LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ IDNO: 723), LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ IDNO: 726), LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ IDNO: 729), LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ IDNO: 732), LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ IDNO: 735), LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ IDNO: 738), GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ IDNO: 741), NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ IDNO: 744), RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ IDNO: 747), YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ IDNO: 750), LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ IDNO: 753), LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ IDNO: 756), LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ IDNO: 759), LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ IDNO: 762), LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ IDNO: 765), LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ IDNO: 768), LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ IDNO: 771), LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ IDNO: 774), LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ IDNO: 777), LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ IDNO: 780), LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ IDNO: 783), LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ IDNO: 786), WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ IDNO: 789), LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ IDNO: 792), LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ IDNO: 795), LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ IDNO: 798), LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ IDNO: 801), LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ IDNO: 804), LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ IDNO: 807), LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ IDNO: 810), SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, orT, or absent. In some embodiments, X₈₀₃ is an optional sequence, and canbe R, F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values. Additionally, a composition cancomprise, consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in Table 5.1. In some embodiments, the isolatedpeptide from Table 5.1 used in these compositions has a length that isless than or equal to 1100 amino acids, for example, less than or equalto 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76,77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94,95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109,110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123,124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137,138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250,260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600,650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids,including ranges between any two of the listed values.

The pharmaceutical composition can comprise one or more otherpharmaceutical acceptable pharmaceutical ingredients, such as apharmaceutically acceptable diluent, carrier, excipient and/or buffer.“Pharmaceutically acceptable” means a non-toxic compound that does notdecrease the effectiveness of the biological activity of the activeingredients. Such pharmaceutically acceptable additives, diluentsbuffers, carriers or excipients are well-known in the art (seeRemington's Pharmaceutical Sciences, 18th edition, A. R Gennaro, Ed.,Mack Publishing Company (1990) and handbook of PharmaceuticalExcipients, 3rd edition, A. Kibbe, Ed., Pharmaceutical Press (2000).

The pharmaceutical composition can include a buffer. The term “buffer”is intended to refer to an aqueous solution containing an acid-basemixture with the purpose of stabilizing pH. Examples of buffering agentsare magnesium hydroxide and aluminum hydroxide; alginic acid;pyrogen-free water; isotonic saline; Ringer's solution; ethyl alcohol;pH buffered solutions; polyesters, polycarbonates and/or polyanhydrides;and other non-toxic compatible substances employed in pharmaceuticalformulations. Other examples of buffers are Trizma, Bicine, Tricine,MOPS, MOPSO, MOBS, Tris, Hepes, HEPBS, MES, phosphate, carbonate,acetate, citrate, glycolate, lactate, borate, ACES, ADA, tartrate, AMP,AMPD, AMPSO, BES, CABS, cacodylate, CHES, DIPSO, EPPS, ethanolamine,glycine, HEPPSO, imidazole, imidazolelactic acid, PIPES, SSC, SSPE,POPSO, TAPS, TABS, TAPSO and TES.

The pharmaceutical composition can include a diluent. The term “diluent”is intended to refer to an aqueous or non-aqueous solution with thepurpose of diluting the compounds in the pharmaceutical preparation. Thediluent may be one or more of saline, water, polyethylene glycol,propylene glycol or ethanol.

The pharmaceutical composition can include an excipient. The excipientcan be one or more of carbohydrates, surfactants, polymers, lipids andminerals. Examples of carbohydrates include lactose, sucrose, mannitol,and cyclodextrines, which are added to the composition, e.g., forfacilitating lyophilisation. Examples of polymers are starch, celluloseethers, cellulose carboxymethylcellulose, hydroxypropylmethyl cellulose,hydroxyethyl cellulose, ethylhydroxyethyl cellulose, alginates,carageenans, hyaluronic acid and derivatives thereof, polyacrylic acid,polysulphonate, polyethylenglycol/polyethylene oxide,polyethyleneoxide/polypropylene oxide copolymers,polyvinylalcohol/polyvinylacetate of different degree of hydrolysis, andpolyvinylpyrrolidone, all of different molecular weight, which are addedto the composition, e.g., for viscosity control, for achievingbioadhesion, or for protecting the lipid from chemical and proteolyticdegradation. Examples of lipids are fatty acids, phospholipids, mono-,di-, and triglycerides, ceramides, sphingolipids and glycolipids, all ofdifferent acyl chain length and saturation, egg lecithin, soy lecithin,hydrogenated egg and soy lecithin, which are added to the compositionfor reasons similar to those for polymers. Examples of minerals aretalc, magnesium oxide, zinc oxide and titanium oxide, which are added tothe composition to obtain benefits such as reduction of liquidaccumulation or advantageous pigment properties.

The pharmaceutical composition can include a carrier. In someembodiments, the carrier is a non-aqueous carrier. Examples of suitableaqueous and nonaqueous carriers which can be employed in thepharmaceutical compositions of the invention include water, ethanol,polyols (such as glycerol, propylene glycol, polyethylene glycol, andthe like), and suitable mixtures thereof, vegetable oils, such as oliveoil, and injectable organic esters, such as ethyl oleate. Properfluidity can be maintained, for example, by the use of coatingmaterials, such as lecithin, by the maintenance of the required particlesize in the case of dispersions, and by the use of surfactants.

These compositions can contain adjuvants such as preservatives, wettingagents, emulsifying agents and dispersing agents. Prevention of theaction of microorganisms upon the subject compounds may be ensured bythe inclusion of various antibacterial and antifungal agents, forexample, paraben, chlorobutanol, phenol sorbic acid, and the like. Itmay also be desirable to include isotonic agents, such as sugars, sodiumchloride, and the like into the compositions. In addition, prolongedabsorption of the injectable pharmaceutical form may be brought about bythe inclusion of agents which delay absorption such as aluminummonostearate and gelatin.

The pharmaceutical composition can be formulated for a extended release.In some embodiments, the pharmaceutical composition is formulated as agel or gel-like substance for extended release. The gel or gel-likesubstance can remain stable under physiological conditions for about 3days, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14 days, 3-4 days, 3-5, 3-6,3-7, 3-8, 3-9, 3-10, 3-11, 3-12, 3-13, 3-14, 4-5, 4-6, 4-7, 4-8, 4-9,4-10, 4-11, 4-12, 4-13, 4-14, 5-6, 5-7, 5-8, 5-9, 5-10, 5-11, 5-12,5-13, 5-14, 6-7, 6-8, 6-9, 6-10, 6-11, 6-12, 6-13, 6-14, 7-8, 7-9, 7-10,7-11, 7-12, 7-13, 7-14, 8-14, 9-14, or 10-14 days. In some embodiments,the gel comprises an inhibitor peptide comprising, consisting of, orconsisting essentially of any of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68,76, 94-96, 98, 264-393, or 583-586, in which the inhibitor peptide isnot water soluble and a buffer or adjuvant selected to formulate a gelwhen combined with the inhibitor peptide. Without being limited by anytheory, in accordance with some embodiments herien, gels can be suitablefor slow release of the inhibitor peptide.

The pharmaceutical composition can be formulated for solubility inaqueous solution. By way of example, an inhibitor peptide consisting ofor consisting essentially of SEQ ID NO: 589 has been shown to be solublein aqueous solution. As such, in some embodiments, a pharmaceuticalcomposition comprises an inhibitor peptide consisting of or consistingessentially of SEQ ID NO: 589 solubilized or partially solubilized in anaqueous solution. Optionally, the aqueous solution can be provided as anadjuvant.

Administration Form

The pharmaceutical formulations described herein may be administeredlocally or systemically. Routes of administration include topical,ocular, nasal, pulmonar, buccal, parenteral (intravenous, subcutaneous,and intramuscular), oral, vaginal and rectal. Most commonly used beingoral administration.

In some embodiments, for example if immune cell invasion of a tumor,cytotoxicity of a tumor, or deblocking of a an immune cell receptor of atumor is desired, the pharmaceutical formulation is administered at ornear a tumor. For example, the pharmaceutical formulation can beadministered peri-tumorally, or within 10 cm of the tumor, for examplewithin 10 cm, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.5 cm of the tumor or arange defined by any two of these distances.

The pharmaceutical compositions will be administered to a patient in atherapeutically effective amount or dose. A therapeutically effectiveamount includes a dose of pharmaceutical composition sufficient to atleast partially arrest a symptom of a disorder from which a patient issuffering. The exact dose is dependent on the manner of administration,the nature and severity of the disorder. Depending on the generalhealth, sex, age and body weight of the patient different doses may beneeded. The administration of the dose can be carried out both by singleadministration in the form of an individual dose unit or else severalsmaller dose units and also by multiple administration of subdivideddoses at specific intervals, for example daily intervals (e.g., 1, 2, 3,4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, or 30 days between doses, including rangesbetween any two of the listed values). Exemplary dosing can comprisedoses in the milligram, microgram, or nanogram-range, for examplemilligrams, micrograms, or nanograms per kg of body weight of thesubject. The active compounds or substances may also be administeredtogether or separately depending on the administration form. Exemplarydosing regiments in accordance with some embodiments herein include“prime boost” approaches in which a first dose of compound or substanceis administered in a first administration, and second dose of compoundor substance is administered in second administration. Optionally,additional subsequent administrations (e.g. third, fourth, fifth, sixth,seventh, eighth, ninth, or tenth) are performed. Optionally, the firstdose is greater than a subsequent dose (e.g. the second dose, or ifperformed, third, fourth, fifth, sixth, seventh, eighth, ninth, ortenth), for example at least 1.1×, 1.2×, 1.5×, 2×, 3×, 4×, 5×, 10×, 20×,30×, 40×, 50×, 100×, 200×, 500×, 1000×, 2000×, 5000×, or 10000× of thesubsequent dose. Optionally, the subsequent dose (e.g. second, third,fourth, fifth, sixth, seventh, eighth, ninth, or tenth) is greater thanthe first dose, for example at least 1.1×, 1.2×, 1.5×, 2×, 3×, 4×, 5×,10×, 20×, 30×, 40×, 50×, 100×, 200×, 500×, 1000×, 2000×, 5000×, or10000× of the first dose. In some embodiments a subsequent dose (e.g.second dose after first dose, third dose after second dose, ifperformed, fourth dose after fifth dose, if performed) is administeredat least one day after the preceding dose, for example, 1, 2, 3, 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,25, 26, 27, 28, 29, 30, 60, 90, or 100 days after, including rangesbetween any two of the listed values.

Suitable preparation forms are, for example granules, powders, tablets,coated tablets, (micro) capsules, microgranulates effervescent powdersor granules, suppositories, injectable solution in ampule form and alsopreparations with protracted release of active compounds, in whosepreparation excipients, diluents or carriers are customarily used asdescribed above. Other preparations may be those which give rise todifferent release profiles of the active ingredients which arewell-known for a person skilled in the art. Examples includesustained-release, sustained-action, extended-release, time-release ortimed-release, controlled-release, modified release, orcontinuous-release. The advantages of sustained-release tablets orcapsules are that they can often be taken less frequently thanimmediate-release formulations of the same drug, and that they keepsteadier levels of the drug in the bloodstream. Today, many time-releasedrugs are formulated so that the active ingredient is embedded in amatrix of insoluble substance(s) (for example some acrylics, or chitin)such that the dissolving drug must find its way out through the holes inthe matrix. Some drugs are enclosed in polymer-based tablets with alaser-drilled hole on one side and a porous membrane on the other side.Stomach acids push through the porous membrane, thereby pushing the drugout through the laser-drilled hole. In time, the entire drug dosereleases into the system while the polymer container remains intact, tobe excreted later through normal digestion. In some formulations, thedrug dissolves into the matrix, and the matrix physically swells to forma gel, allowing the drug to exit through the gel's outer surface.Micro-encapsulation is also regarded as a more complete technology toproduce complex dissolution profiles. Through coating an activepharmaceutical ingredient around an inert core, and layering it withinsoluble substances to form a microsphere it is possible to obtain moreconsistent and replicable dissolution rates. In some embodiments, thecomposition comprises at least about at least 0.1% of theimmunoregulatory peptide inhibitor by weight, for example, at least0.1%, 0.2%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20%, or 30%of the immunoregulatory peptide inhibitor by weight, including rangesbetween any two of the listed values. All of those being well-known fora person skilled in the art.

Methods of Detecting the Presence of an Albumin or Albumin Fragment

Some embodiments include methods of detecting the presence of an albuminor albumin fragment in a biological sample by contacting animmunoregulatory peptide inhibitor with the biological sample therebyallowing the binding of the immunoregulatory peptide inhibitor to thealbumin or albumin fragment and detecting the presence of the boundimmunoregulatory peptide inhibitor. In some embodiments, a method ofdetecting the presence of the P3028 sequence/structure or a fragmentthereof can include contacting a biological sample comprising the P3028sequence/structure with an immunoregulatory peptide inhibitor orantibody that binds to the P3028 sequence/structure and detecting thepresence of the bound immunoregulatory peptide inhibitor. Optionally,the immunoregulatory peptide inhibitor or antibody comprises adetectable moiety as described herein.

The immunoregulatory peptide inhibitor used in these methods cancomprise, consist of, or consist essentially of a peptide as describedherein. For example, the peptide inhibitor can comprise, consist of, orconsist essentially of Formula (I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166) asdescribed herein. In some embodiments, X is an optional sequence, andcan be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO:169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO:252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO:255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO:258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO:260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO:263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, or Q, or absent. In someembodiments, X₁ is one of FF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT,AL, VF, VM, VS, VV, VT, or VL. In some embodiments, X₂ is one of LS, LQ,LM, LT, LH, VS, VQ, VM, VT, or VH. In some embodiments, X₃ is one ofLFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT,QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT,VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN,LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN,QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN,MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP,LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP,QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP,MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR,LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR,QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR,MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR. In some embodiments, X₄is an optional sequence, and can be ER, or E, or absent. In someembodiments, if X is absent, X₁ is FF, and X₂ is LS. In someembodiments, the isolated peptides that comprise Formula (I) used inthese methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173). In some embodiments, X₂₀ is an optional sequence, andcan be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO:176), KKED (SEQ ID NO: 177), KLD, LD, or D, or absent. X₂₁ is anoptional sequence, and can be LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT,LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT,VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT,MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN,QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN,VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN,MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP,QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP,VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR(SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR,QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR,VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, orMRR, or absent. In some embodiments, X₂₂ is an optional sequence, andcan be ER, or E, or absent. In some embodiments, the isolated peptidesthat comprise Formula (II) used in these methods have a length that isless than or equal to 1100 amino acids, for example, less than or equalto 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76,77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94,95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109,110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123,124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137,138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250,260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600,650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids,including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. Additionally, the peptideinhibitor can comprise, consist of, or consist essentially of and/or SEQID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96 or 98, as describedherein. In some embodiments, the isolated peptides that comprise Formula(III) used in these methods have a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (IX). Accordingly, in someembodiments, the peptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally, X₉₀₁ is an R or K. Optionally, X₉₁₇ is RR. Insome embodiments, the isolated peptide comprising Formula (IX) has alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of and/or SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 as describedherein. In some embodiments, these isolated peptides used in thesemethods have a length that is less than or equal to 1100 amino acids,for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68,69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86,87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103,104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117,118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131,132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190,200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360,380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000,1050, or 1100 amino acids, including ranges between any two of thelisted values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in or any one or more of the peptides provided inTable 5.1, 5.4, 5.5, 5.6, or any variation or combination of variationsof P28R or P28 core as provided in Tables 5.3 and 13. In someembodiments, the isolated peptide from in or any one or more of thepeptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13 used in these methods has a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values.

Accordingly, once the immunoregulatory peptide inhibitor is bound to analbumin fragment or albumin comprising the P3028 sequence/structure, thepresence of the inhibitor is detected, thus detecting the presence ofthe P3028 sequence/structure.

In some methods for detecting the presence of albumin or an albuminfragment comprising the P3028 sequence/structure, the immunoregulatorypeptide inhibitor comprises a peptide that comprises, consists of, orconsists essentially of a peptide as described herein. For example, thepeptide inhibitor used in these methods can comprise, consist of, orconsist essentially of Formula (I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166) asdescribed herein. In some embodiments, X is an optional sequence, andcan be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO:169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO:252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO:255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO:258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO:260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO:263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, or Q, or absent. In someembodiments, X₁ is one of FF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT,AL, VF, VM, VS, VV, VT, or VL. In some embodiments, X₂ is one of LS, LQ,LM, LT, LH, VS, VQ, VM, VT, or VH. In some embodiments, X₃ is one ofLFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT,QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT,VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN,LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN,QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN,MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP,LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP,QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP,MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR,LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR,QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR,MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR. In some embodiments, X₄is an optional sequence, and can be ER, or E, or absent. In someembodiments, if X is absent, X₁ is FF, and X₂ is LS. In someembodiments, the isolated peptides that comprise Formula (I) used inthese methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173). In some embodiments, X₂₀ is an optional sequence, andcan be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO:176), KKED (SEQ ID NO: 177), KLD, LD, D, or absent. X₂₁ is an optionalsequence, and can be LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT,QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT,VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT,MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN,QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN,VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN,LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP,QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP,VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO:815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR,QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR,VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR, orabsent. In some embodiments, X₂₂ is an optional sequence, and can be ER,or E, or absent. In some embodiments, the isolated peptides thatcomprise Formula (II) used in these methods have a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. Additionally, the peptideinhibitor can comprise, consist of, or consist essentially of and/or SEQID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96 or 98 as described herein.In some embodiments, the isolated peptides that comprise Formula (III)used in these methods have a length that is less than or equal to 1100amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10,11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28,29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46,47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82,83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100,101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114,115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128,129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160,170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300,320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850,900, 950, 1000, 1050, or 1100 amino acids, including ranges between anytwo of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (IX). Accordingly, in someembodiments, the peptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of and/or SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 as described herein. In some embodiments, theseisolated peptides used in these methods have a length that is less thanor equal to 1100 amino acids, for example, less than or equal to 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96,97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125,126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139,140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270,280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700,750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in Table 5.1. In some embodiments, the isolatedpeptide from Table 5.1 used in these methods has a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

In some embodiments, the immunoregulatory peptide inhibitor is attachedto a support (see Example 12). Exemplary supports include surfaces, atest strip, petri dish, matrices, resin, or beads. In some embodiments,the immunoregulatory peptide inhibitor is dissolved in solution (seeExample 10). In some embodiments, a biological sample possiblycontaining the P3028 sequence/structure is contacted with the inhibitorin solution (see Examples 10 and 12). The biological sample can includeblood, serum, immune cells, immune cell lysates, tumor cells, or tumorcell lysates. After contact with the immunoregulatory peptide inhibitor,the support having the protein complex disposed thereon is optionallywashed so as to remove any unbound or loosely affixed immunoregulatorypeptide inhibitor. If the P3028 sequence/structure was present in thesample, the presence of the P3028 sequence/structure bound to theinhibitor attached to the support is detected, for example using a rampoassay. If the P3028 sequence/structure was not present in the sample, nobound protein is detected.

In some embodiments, the immunoregulatory peptide inhibitor is attachedto a detectable label, as described herein. Exemplary detectable labelsinclude biotin, fluorophores, radiolabels, and enzymes. In someembodiments, a biological sample that possibly contains the P3028sequence/structure is provided. The sample can include, blood, plasma,serum, isolated immune cells, isolated cancer cell, a tissue biopsy,and/or a tumor biopsy. The inhibitor of peptide 3028 (theimmunoregulatory peptide inhibitor) is contacted with the biologicalsample. The sample then can be optionally washed. If the P3028sequence/structure is present, the detectable label will be present inthe biological sample (see Example 14). If the P3028 sequence/structurewas not present, no label is detected. Exemplary methods of detectingthe detectable label include microscopy, histological sectioning,immunoassays, immunohistochemistry, flow cytometry, immunoblotting,ELISA, and ELISpot (see FIG. 39). For example, a histological sectioncan be examined to determine cells and/or tissues that contain the P3028sequence/structure. For example, a sample of dissociated immune and/ortumor cells can be screened for cells bound to the P3028sequence/structure using frozen or plastic section techniques. Thesection below provides more detail on approaches to treat, prevent, orinhibit immunosuppression in a subject in need thereof (e.g., a subjectthat has cancer or a pathogenic infection, such as a viral infection ora bacterial infection).

Method of Treating, Preventing, or Inhibiting Immunosuppression

Many conditions and diseases are associated with immunosuppression, forexample, many types of cancer, infection, and inflammatory disease areassociated with immunosuppression. Thus, exemplary conditions associatedwith immunosuppression that can be treated, prevented, or inhibitedusing one or more of the immunoregulatory peptide inhibitors describedherein include many types of cancer, such as colorectal cancer, renalcancer, breast cancer, skin cancer, ovarian cancer, prostate cancer,pancreatic cancer, lung cancer, or hematopoietic cell cancer. Theseconditions can also be treated, prevented, ameliorated, or inhibitedusing one or more of the immunoregulatory peptide inhibitors describedherein. Exemplary conditions associated with immunosuppression that canbe treated, prevented, or inhibited by using one or more of theimmunoregulatory peptide inhibitors described herein further includehormonal imbalances, such as increased and/or ectopic cortisol activity.

Accordingly, some embodiments include methods of treating, preventing,or reducing immunosuppression or one or more of the aforementionedinfections or diseases in a human. In some embodiments, the methodincludes identifying a patient having a condition associated withimmunosuppression (e.g., cancer). Such an identification step can beaccomplished by clinical evaluation (e.g., CT, MRI, or PET scan) ordiagnostic assay. The method further includes administering to theidentified or selected patient a composition comprising, consisting of,or consisting essentially of an immunoregulatory peptide inhibitorsequence, or a nucleic acid encoding such a molecule as describedherein. For example, the composition comprising, consisting of, orconsisting essentially of an immunoregulatory peptide inhibitor caninclude any one of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96,98, 264-393, 583-586, or 589 or any one or more of the peptides providedin Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13. In someembodiments, the composition is administered peri-tumorally, or near atumor, for example within 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.5 cm of atumor. In some embodiments, the composition is administeredsystemically. In some embodiments, the composition is administered inconjunction with a second therapeutic agent, for example a therapeuticagent selected to stimulate an immune cell after an LFA-1 receptor ofthe immune cell has been de-blocked (e.g. bound immunoregulatorypeptides or 3028 structures have been displaced from the LFA-1receptor). In some embodiments, these isolated peptides used in thesemethods have a length that is less than or equal to 1100 amino acids,for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68,69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86,87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103,104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117,118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131,132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190,200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360,380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000,1050, or 1100 amino acids, including ranges between any two of thelisted values.

Additionally, the composition comprising, consisting of, or consistingessentially of the immunoregulatory peptide inhibitor used in thesemethods can comprise, consist of, or consist essentially of a peptide asdescribed herein, or a nucleic acid encoding such a molecule. Forexample, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (I), XX₁VKX₂X₃X₄ (SEQ IDNO: 166) as described herein. In some embodiments, X is an optionalsequence, and can be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO: 168),KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO: 171),KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO: 254),RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO: 257),RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO: 259),KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO: 262),KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, or Q, orabsent. In some embodiments, X₁ is one of FF, FM, FS, FV, FT, FL, AF,AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, or VL. In some embodiments, X₂is one of LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH. In someembodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT,LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT,VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST,MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN,QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN,VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN,MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP,QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP,VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ IDNO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR,QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR,VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR.In some embodiments, X₄ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, if X is absent, X₁ is FF, and X₂ is LS. Insome embodiments, the isolated peptides that comprise Formula (I) usedin these methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173), as described herein. In some embodiments, X₂₀ is anoptional sequence, and can be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO:175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO: 177), KLD, LD, D, orabsent. X₂₁ is an optional sequence, and can be LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR, or absent. In some embodiments, X₂₂ is anoptional sequence, and can be ER, or E, or absent. In some embodiments,the isolated peptides that comprise Formula (II) used in these methodshave a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. In some embodiments, theisolated peptides that comprise Formula (III) used in these methods havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of Formula(IX). Accordingly, in some embodiments, thepeptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of and/or SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13. In some embodiments, these isolated peptides usedin these methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96, 98, 264-393, 583-586, or 589 or any one or more of the peptidesprovided in Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13. In someembodiments, the isolated peptide used in these methods has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

In some embodiments, a nucleic acid encoding such a peptide inhibitorcan be provided, for example a nucleic acid of SEQ ID NOs: 102-165.Preferably, the immunoregulatory peptide inhibitor used in theaforementioned methods is P28R, a derivative thereof, or a nucleic acidencoding such a molecule (e.g., any one or more of the immunoregulatorypeptide inhibitors comprise, consist of, or consist essentially of apeptide as described herein. For example, the peptide inhibitor cancomprise, consist of, or consist essentially of Formula (I), XX₁VKX₂X₃X₄(SEQ ID NO: 166) as described herein. In some embodiments, X is anoptional sequence, and can be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO:168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO:171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO:254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO:257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO:259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO:262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, orQ, or absent. In some embodiments, X₁ is one of FF, FM, FS, FV, FT, FL,AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, or VL. In some embodiments,X₂ is one of LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH. In someembodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT,LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT,VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST,MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN,QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN,VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN,MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP,QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP,VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ IDNO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR,QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR,VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR.In some embodiments, X₄ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, if X is absent, X₁ is FF, and X₂ is LS. Insome embodiments, the isolated peptides that comprise Formula (I) have alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂ (SEQ ID NO: 173). In someembodiments, X₂₀ is an optional sequence, and can be KKLD (SEQ ID NO:174), RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO:177), KLD, LD, or D, or absent. X₂₁ is an optional sequence, and can beLFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT,QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT,VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN,LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN,QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN,MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP,LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP,QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP,MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR,LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR,QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR,MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR, or absent. In someembodiments, X₂₂ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, the isolated peptides that comprise Formula(II) have a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of Formula (III), X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). Insome embodiments, X₃₀ is an optional sequence, and can be KKLDTF (SEQ IDNO: 179), KLDTF (SEQ ID NO: 180), LDTF (SEQ ID NO: 181), DTF, TF, F, orabsent. In some embodiments, X₃₁ is an optional sequence, and can be F,S, M, V, T, or L, or absent. In some embodiments, X₃₁ is F. In someembodiments, X₃₂ can be S, Q, M, T, or H. In some embodiments, X₃₂ is S.X₃₃ can be F, M, Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ isF. X₃₄ is an optional sequence, and can be R or absent. In someembodiments, the isolated peptides that comprise Formula (III) have alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃ X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), as described herein. In someembodiments, X₇₀₀ is an optional sequence, and can be K, A, D, E, G, H,I, L, M, N, P, Q, R, T, or V, or absent. In some embodiments, X₇₀₁ is anoptional sequence, and can be L, A, C, D, E, F, G, H, I, K, M, N, Q, R,S, T, or V, or absent. In some embodiments, X₇₀₂ is an optionalsequence, and can be D, A, E, I, V, W, or Y, or absent. In someembodiments, X₇₀₃ is an optional sequence, and can be T, C, M, N, P, Q,R, S, W, or Y, or absent. In some embodiments, X₇₀₄ is an optionalsequence, and can be F, A, I, M, N, P, T, or V, or absent. In someembodiments, X₇₀₅ is an optional sequence, and can be F, L, M, Q, S, TV,or absent. In some embodiments, X₇₀₆ is an optional sequence, and can beV, F, G, L, P, or R, or absent. In some embodiments, X₇₀₇ is an optionalsequence, and can be L, A, F, G, I, M, N, P, Q, R, S, T, V, or Y, orabsent. In some embodiments, X₇₀₈ is an optional sequence, and can be S,H, M, N, Q, or T, or absent. In some embodiments, X₇₀₉ is an optionalsequence, and can be L, A, H, I, M, N, Q, R, S, T, V, or W, or absent.In some embodiments, X₇₁₀ is an optional sequence, and can be F, A, C,G, H, I, L, M, N, P, Q, R, S, T, V, or W, or absent. In someembodiments, X₇₁₁ is an optional sequence, and can be T, F, G, H, I, L,M, N, P, S, V, or W, or absent. In some embodiments, X₇₁₂ is an optionalsequence, and can be R, F, K, N, R, T,+ or Y, or absent. In someembodiments, the isolated peptide comprising Formula (VII) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂E X₈₀₃ (SEQ ID NO: 395),as described herein. In some embodiments, X₈₀₀ is an optional sequence,and can be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, V, or K, or absent.In some embodiments, X₈₀₁ is an optional sequence, and can be LDTFFV(SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597), EDTFFV (SEQ ID NO: 598),LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO: 600), LDTVFV (SEQ ID NO:601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ ID NO: 603), LDTFVV (SEQ IDNO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQ ID NO: 606), LDGFFV (SEQID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK (SEQ ID NO: 609), ADTFFV(SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611), DDTFFV (SEQ ID NO: 612),FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO: 614), IDTFFV (SEQ ID NO:615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ ID NO: 617), NDTFFV (SEQ IDNO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQ ID NO: 620), SDTFFV (SEQID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV (SEQ ID NO: 623), LATFFV(SEQ ID NO: 624), LETFFV (SEQ ID NO: 625), LITFFV (SEQ ID NO: 626),LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO: 628), LYTFFV (SEQ ID NO:629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ ID NO: 631), LDNFFV (SEQ IDNO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQ ID NO: 634), LDSFFV (SEQID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV (SEQ ID NO: 637), LDTIFV(SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639), LDTNFV (SEQ ID NO: 640),LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO: 642), LDTFQV (SEQ ID NO:643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ ID NO: 645), LDTFFL (SEQ IDNO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQ ID NO: 648), LDTFIV (SEQID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV (SEQ ID NO: 651), LDTFCV(SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653), LDTLFV (SEQ ID NO: 654),LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO: 656), LDHFFV (SEQ ID NO:657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ ID NO: 659), LDTFWV (SEQ IDNO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQ ID NO: 662), LDTFRV (SEQID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV (SEQ ID NO: 665), LPTFFV(SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667), LDTFPV (SEQ ID NO: 668),LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO: 670), LDTGFV (SEQ ID NO:671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ ID NO: 673), LCTFFV (SEQ IDNO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQ ID NO: 676), LDEFFV (SEQID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV (SEQ ID NO: 679), LDTCFV(SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681), LDTHFV (SEQ ID NO: 682),LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO: 684), LDLFFV (SEQ ID NO:685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ ID NO: 687), LDTFDV (SEQ IDNO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQ ID NO: 690), LNTFFV (SEQID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV (SEQ ID NO: 693), LDFFFV(SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695), LDTFFQ (SEQ ID NO: 696),LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO: 698), LDKFFV (SEQ ID NO:699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ ID NO: 701), LDTFFW (SEQ IDNO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQ ID NO: 704), LDTFFH (SEQID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN (SEQ ID NO: 707), LDTDFV(SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709), LDTFFD (SEQ ID NO: 710),LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712), TFFV (SEQ ID NO: 713),LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L, or absent. In someembodiments, X₈₀₂ is an optional sequence, and can be LSLFT (SEQ ID NO:715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717), LMLFT (SEQ ID NO:718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720), LSQFT (SEQ ID NO:721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723), LSLMT (SEQ ID NO:724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726), LSLNT (SEQ ID NO:727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729), LSLGT (SEQ ID NO:730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732), LSLFN (SEQ ID NO:733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735), LGLFT (SEQ ID NO:736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738), GSLFT (SEQ ID NO:739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741), NSLFT (SEQ ID NO:742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744), RSLFT (SEQ ID NO:745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747), YSLFT (SEQ ID NO:748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750), LSHFT (SEQ ID NO:751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753), LSRFT (SEQ ID NO:754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756), LSWFT (SEQ ID NO:757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759), LSLLT (SEQ ID NO:760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762), LSLWT (SEQ ID NO:763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765), LSLFH (SEQ ID NO:766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768), LSLFM (SEQ ID NO:769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771), LSLFW (SEQ ID NO:772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774), LSFFT (SEQ ID NO:775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777), LSCFT (SEQ ID NO:778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780), LPLFT (SEQ ID NO:781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783), LDLFT (SEQ ID NO:784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786), WSLFT (SEQ ID NO:787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789), LSPFT (SEQ ID NO:790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792), LILFT (SEQ ID NO:793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795), LSLFY (SEQ ID NO:796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798), LFLFT (SEQ ID NO:799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801), LLLFT (SEQ ID NO:802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804), LSLFE (SEQ ID NO:805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807), LSDFT (SEQ ID NO:808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810), SLFT (SEQ ID NO:811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, or absent. In someembodiments, X₈₀₃ is an optional sequence, and can be R, F, K, N, R, T,or Y, or absent. In some embodiments, the isolated peptide comprisingFormula (VIII) has a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of Formula(IX). Accordingly, in some embodiments, thepeptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of and/or SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96,98, 264-393, 583-586, or 589 or any one or more of the peptides providedin Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13, asdescribed herein. In some embodiments, the isolated peptides have alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of a peptide inhibitor that comprises, consists of, orconsists essentially of any one or more of the peptides set forth inTable 5.1, 5.4, 5.5, or 5.6 or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13 In someembodiments, the isolated peptide from Table 5.1, 5.4, 5.5, or 5.6 orany variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13 has a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values. For example, a nucleic acid encoding sucha peptide inhibitor can be provided, by SEQ ID NOs: 102-165.

The immunoregulatory peptide inhibitors used in the aforementionedmethods can comprise at least one D amino acid, at least one non-naturalamino acid, an N-terminal acetyl group, or a C terminal amide group andsaid immunoregulatory peptide inhibitors can be glycosylated or joinedto PEG, a cytotoxin, or radionuclide. The peptide can be administered toat least one cell of the patient. The administration can be performed invivo, for example therapeutically. The administration can be performedex vivo, for example as a diagnostic tool, or as an ex vivo therapy tostimulate immune cells of the patient before the immune cells areadministered to the patient. Administration of an immunoregulatorypeptide inhibitor comprising, consisting, or consisting essentially of apeptide inhibitor as described herein, or a nucleic acid encoding such amolecule to human immune cells, and detection of immune cell stimulationis described in Example 13). For example, the peptide inhibitor used inthese methods can comprise, consist of, or consist essentially ofFormula (I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166) as described herein. In someembodiments, X is an optional sequence, and can be KKLDT (SEQ ID NO:167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO:170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO:253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO:256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO:172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO:261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ,EDT, EDQ, DT, DQ, T, or Q, or absent. In some embodiments, X₁ is be oneof FF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT,or VL. In some embodiments, X₂ is one of LS, LQ, LM, LT, LH, VS, VQ, VM,VT, or VH. In some embodiments, X₃ is be one of LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR. In some embodiments, X₄ is an optional sequence,and can be ER, or E, or absent. In some embodiments, if X is absent, X₁is FF, and X₂ is LS. In some embodiments, the isolated peptides thatcomprise Formula (I) used in these methods have a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173). In some embodiments, X₂₀ is an optional sequence, andcan be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO:176), KKED (SEQ ID NO: 177), KLD, LD, or D, or absent. X₂₁ is anoptional sequence, and can be LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT,LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT,VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT,MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN,QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN,VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN,MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP,QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP,VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR(SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR,QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR,VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, orMRR, or absent. In some embodiments, X₂₂ is an optional sequence, andcan be ER, or E, or absent. In some embodiments, the isolated peptidesthat comprise Formula (II) used in these methods have a length that isless than or equal to 1100 amino acids, for example, less than or equalto 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76,77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94,95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109,110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123,124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137,138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250,260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600,650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids,including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. In some embodiments, theisolated peptides that comprise Formula (III) used in these methods havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, and canbe T, C, M, N, P, Q, R, S, W, Y, or absent. In some embodiments, X₇₀₄ isan optional sequence, and can be F, A, I, M, N, P, T, or V, or absent.In some embodiments, X₇₀₅ is an optional sequence, and can be F, L, M,Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor can comprise, consist of, or consistessentially of and/or SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96,98, 264-393, 583-586, or 589 or any one or more of the peptides providedin Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13, asdescribed herein. In some embodiments, these isolated peptides used inthese methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in Table 5.1. In some embodiments, the isolatedpeptide from Table 5.1 used in these methods has a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

A nucleic acid encoding such a peptide inhibitor can be provided, forexample a nucleic acid of SEQ ID NOs: 102-165. Following administrationof the immunoregulatory peptide inhibitor, stimulation of human immunecells of the human can be detected (e.g., an increase in immune cellproliferation, migration of NK cell cytotoxicity). Once theimmunoregulatory peptide inhibitor has been administered, these methodscan, optionally, include measuring or observing a reduction inimmunosuppression in the patient (e.g., an increase in immune cellproliferation, migration, or spreading or NK-cell cytotoxicity can beevaluated or detecting activation or stimulation of an immune cell, asevidenced by an increase in CD69 or CD71 expression, induction of thesecretion of a signal substance, as evidenced by interferon gamma orIL-12 production, or stimulation of the release of a cytolyticsubstance, as evidenced by the release of granzyme B or perforin,enhanced cytotoxicity, cytokine production, cell migration, and/or cellproliferation).

As mentioned above, some embodiments include a step of identifying apatient suffering from immunosuppression. This analysis can includegenerally determining the immune cell activity of the patient, forexample determining the quantity of at least one immune cell type, forexample leukocytes, PBMC's, lymphocytes, monocytes, macrophages in abiological sample of the patient. The presence of the P3028sequence/structure in the serum of a patient, and/or on a cancer cell ofa patient (an evaluation that can be accomplished using a labeledimmunoregulatory peptide inhibitor) is also indicative of suppression ofthe immune system of the patient. Accordingly, some embodiments of theinvention include detecting the presence of the P3028 sequence/structurein a biological sample of a patient, for example a sample that includesblood, plasma, serum, or a cancer cell biopsy. Examples, methods, andcompositions for detecting the presence of Peptide 3028 in a biologicalsample of a patient can be found in U.S. Pat. Nos. 7,960,126, 8,133,688,8,110,347, and US Publication Nos. 2010/0323370 and 2011/0262470, eachof which is hereby expressly incorporated by reference in its entirety.The P3028 sequence/structure can be detected, for example, byimmunoassays, a blotting technique, ELISA, ELISpot, flow cytometry,cytometric bead assay, proteomics, and/or immunohistochemistry of abiological sample, using at least one antibody that binds to the P3028sequence/structure. The P3028 sequence/structure can also be detected,for example, by mass spectrometry of a biological sample of a patient ora fraction thereof. The P3028 sequence/structure can further be detectedby direct detection of a labeled peptide inhibitor of the P3028sequence/structure as described herein, for example by histologicalstaining, fluorescent microscopy, immunohistochemistry, or colorimetricenzymatic assays (see Example 14). The P3028 sequence/structure can alsobe detected, for example, functionally, by comparing an immune cellcontacted by a patient's serum to an immune cell contacted by controlsample serum known not to contain the P3028 sequence/structure. In someembodiments, the serum is denatured. Exemplary immune cells includePBMCs. In some embodiments, the serum is not denatured. The immune cellscan be optionally stimulated, for example, by IL-2 or lipopolysaccharide(LPS). In some embodiments, the immune cells are analyzed for IL-6production.

In some embodiments, a patient suffering from immunosuppression can beidentified by diagnosing the patient with cancer. In some embodiments,cancer cells can be identified, and the patient can thus be identified,by detecting the binding of cells of the patient to the P3028sequence/structure (see Example 7) or an inhibitor of the P3028sequence/structure (see Example 14). Exemplary cancers that can beidentified, and that are associated with immunosuppression includebreast cancer, renal cell carcinoma, and malignant melanoma.

The administration of the immunoregulatory peptide inhibitor to thepatient can be accomplished by a variety of approaches. In someembodiments, the immunoregulatory peptide inhibitor is administereddirectly to the patient. The immunoregulatory peptide inhibitor can beadministered intravenously, intraperitoneally, subcutaneousously,intramuscularly, topically, transdermally, orally, and/orperi-tumorally. In some embodiments, the immunoregulatory peptideinhibitor is administered at the site of a tumor, for example via directinjection. In some embodiments, the immunoregulatory peptide inhibitoris administered near a tumor, for example within 10 cm, 9 cm, 8 cm, 7cm, 6 cm, 5 cm, 4 cm, 3 cm, 2 cm, 1 cm, or 0.5 cm of the tumor or arange defined by any tow of the aforementioned distances. In someembodiments, the immunoregulatory peptide inhibitor is administered witha pharmaceutically acceptable diluent or carrier, as described herein.In some embodiments, the immunoregulatory peptide inhibitor isadministered ex vivo. Immune cells of the patient can be isolated fromthe patient, contacted with the inhibitor, and returned to the patient,for example. Examples 13 and 14 describe contacting immune cells of apatient with an inhibitor of the P3028 sequence/structure.

Any one or more of the immunoregulatory peptide inhibitors describedherein can be employed with one or more of the aforementioned methods.In some embodiments, the immunoregulatory peptide inhibitor comprises atleast one of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98,264-393, 583-586, or 589 or any one or more of the peptides provided inTable 5.1, 5.4, 5.5, 5.6, or any variation or combination of variationsof P28R or P28 core as provided in Tables 5.3 and 13. In someembodiments, the immunoregulatory peptide inhibitor includes at leastone peptidomimetic inhibitor of the P3028 sequence/structurecorresponding to any one or more of SEQ ID NOs: 1-33, 34, 46-53, 64-66,68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one or more of thepeptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13. In some embodiments, the immunoregulatory peptide inhibitor is asmall molecule inhibitor of Peptide 3028 corresponding to any one ormore of SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393,583-586, or 589 or any one or more of the peptides provided in Table5.1, 5.4, 5.5, 5.6, or any variation or combination of variations ofP28R or P28 core as provided in Tables 5.3 and 13. In some embodiments,the immunoregulatory peptide inhibitor includes an antibody or fragmentthereof that specifically binds to the P3028 sequence/structure.Antibodies that inhibit the P3028 sequence/structure are described inExample 9.

In some of the aforementioned methods, the immunoregulatory peptideinhibitor of the P3028 sequence/structure comprises a nucleic acidencoding an immunoregulatory peptide inhibitor, such as a peptidedescribed herein. For example, the peptide inhibitor encoded by thenucleic acid can comprise, consist of, or consist essentially of Formula(I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166) as described herein. In someembodiments, X is an optional sequence, and can be KKLDT (SEQ ID NO:167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO:170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO:253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO:256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO:172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO:261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ,EDT, EDQ, DT, DQ, T, or Q, or absent. In some embodiments, X₁ is one ofFF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, orVL. In some embodiments, X₂ is one of LS, LQ, LM, LT, LH, VS, VQ, VM,VT, or VH. In some embodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR. In some embodiments, X₄ is an optional sequence,and can be ER, or E, or absent. In some embodiments, if X is absent, X₁is FF, and X₂ is LS. In some embodiments, the isolated peptides thatcomprise Formula (I) encoded by the nucleic acids used in these methodshave a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor encoded by the nucleic acids cancomprise, consist of, or consist essentially of Formula (II),X₂₀TFFVKLSX₂₁X₂₂ (SEQ ID NO: 173). In some embodiments, X₂₀ is anoptional sequence, and can be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO:175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO: 177), KLD, LD, or D, orabsent. X₂₁ is an optional sequence, and can be LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR, or absent. In some embodiments, X₂₂ is anoptional sequence, and can be ER, E, or absent. In some embodiments, theisolated peptides that comprise Formula (II) encoded by the nucleicacids used in these methods have a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values.

Additionally, the peptide inhibitor encoded by the nucleic acids cancomprise, consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. In some embodiments, theisolated peptides that comprise Formula (III) encoded by the nucleicacids used in these methods have a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values.

Additionally, the peptide inhibitor encoded by the nucleic acids cancomprise, consist of, or consist essentially of Formula (VII), X₇₀₀KX₇₀₁X₇₀₂X₇₀₃ X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO:394), as described herein. In some embodiments, X₇₀₀ is an optionalsequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, orabsent. In some embodiments, X₇₀₁ is an optional sequence, and can be L,A, C, D, E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor encoded by the nucleic acids cancomprise, consist of, or consist essentially of Formula (VIII), X₈₀₀KX₈₀₁K X₈₀₂E X₈₀₃ (SEQ ID NO: 395), as described herein. In someembodiments, X₈₀₀ is an optional sequence, and can be K, A, D, E, G, H,I, L, M, N, P, Q, R, T, V, or K, or absent. In some embodiments, X₈₀₁ isan optional sequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ IDNO: 597), EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQID NO: 600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV(SEQ ID NO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605),LDTFLV (SEQ ID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO:608), LDTFFK (SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ IDNO: 611), DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQID NO: 614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV(SEQ ID NO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619),RDTFFV (SEQ ID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO:622), VDTFFV (SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ IDNO: 625), LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQID NO: 628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV(SEQ ID NO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633),LDRFFV (SEQ ID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO:636), LDYFFV (SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ IDNO: 639), LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQID NO: 642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG(SEQ ID NO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647),LDTFFR (SEQ ID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO:650), LDTFAV (SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ IDNO: 653), LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQID NO: 656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV(SEQ ID NO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661),LDVFFV (SEQ ID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO:664), LDTYFV (SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ IDNO: 667), LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQID NO: 670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV(SEQ ID NO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675),YDTFFV (SEQ ID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO:678), LDTKFV (SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ IDNO: 681), LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQID NO: 684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV(SEQ ID NO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689),LDTFFT (SEQ ID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO:692), LDIFFV (SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ IDNO: 695), LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQID NO: 698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV(SEQ ID NO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703),LDTFFS (SEQ ID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO:706), LDTFFN (SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ IDNO: 709), LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ IDNO: 712), TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV,LV, or L, or absent. In some embodiments, X₈₀₂ is an optional sequence,and can be LSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ IDNO: 717), LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ IDNO: 720), LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ IDNO: 723), LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ IDNO: 726), LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ IDNO: 729), LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ IDNO: 732), LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ IDNO: 735), LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ IDNO: 738), GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ IDNO: 741), NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ IDNO: 744), RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ IDNO: 747), YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ IDNO: 750), LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ IDNO: 753), LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ IDNO: 756), LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ IDNO: 759), LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ IDNO: 762), LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ IDNO: 765), LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ IDNO: 768), LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ IDNO: 771), LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ IDNO: 774), LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ IDNO: 777), LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ IDNO: 780), LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ IDNO: 783), LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ IDNO: 786), WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ IDNO: 789), LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ IDNO: 792), LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ IDNO: 795), LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ IDNO: 798), LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ IDNO: 801), LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ IDNO: 804), LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ IDNO: 807), LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ IDNO: 810), SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, orT, or absent. In some embodiments, X₈₀₃ is an optional sequence, and canbe R, F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor encoded by the nucleic acid used inthese methods can comprise, consist of, or consist essentially ofFormula (IX). Accordingly, in some embodiments, the peptide inhibitorcomprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor encoded by the nucleic acid used inthese methods can comprise, consist of, or consist essentially of and/orSEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586,or 589 or any one or more of the peptides provided in Table 5.1, 5.4,5.5, 5.6, or any variation or combination of variations of P28R or P28core as provided in Tables 5.3 and 13, as described herein. In someembodiments, these isolated peptides encoded by the nucleic acids usedin these methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor encoded by the nucleic acid used inthese methods can comprise, consist of, or consist essentially of apeptide inhibitor that comprises, consists of, or consists essentiallyof any one or more of the peptides set forth in Table 5.1, 5.4, 5.5,5.6, or any variation or combination of variations of P28R or P28 coreas provided in Tables 5.3 and 13. In some embodiments, the isolatedpeptide from Table 5.1 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13, whichis encoded by the nucleic acid used in these methods has a length thatis less than or equal to 1100 amino acids, for example, less than orequal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56,57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108,109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122,123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136,137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240,250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550,600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids,including ranges between any two of the listed values.

For example, a nucleic acid encoding such a peptide inhibitor can beprovided, for example a nucleic acid of SEQ ID NOs: 102-165. The nucleicacid can be provided in an expression vector as described herein. Thenucleic acid can be provided to the human by directly administering anexpression vector comprising the nucleic acid that encodes theimmunoregulatory peptide inhibitor to the human, for example via aretroviral or adenoviral vector or expression plasmid used in geneticimmunization (e.g., pVAX). The expression vector can be provided tocells of the human ex vivo, and the cells can be returned to the humanor in vivo using electroporation technology. Methods of deliveringnucleic acids to a host cell via viral vectors are described in U.S.Pat. No. 7,572,906, which is expressly incorporated by reference in itsentirety herein. Methods of transducing immune cells with an adenovirusex vivo and returning them to a patient are described in U.S. Pat. No.8,012,468, which is expressly incorporated by reference in its entiretyherein. In some embodiments, a host cell, is contacted with a vectorencoding the immunoregulatory peptide inhibitor of P3028. The vector canreplicates in the host cell. In some embodiments, the host cell is alsocontacted with a “helper-expression vector,” i.e., a viral genome thatpromotes the replication of the vector in an uninfected host. In someembodiments, the inhibitor is administered as in Example 16. In someembodiments, the cell is contacted ex vivo. In some embodiments, thecell is an immune cell. In some embodiments, the cell is one of alymphocyte, a PBMC, or a leukocyte. In some embodiments, the inhibitoris administered as in Example 13.

Preferably, a therapeutically effective amount of the immunoregulatorypeptide inhibitor is provided. For a patient already suffering fromP3028-dependent immunosuppression, a therapeutically effective amount ofinhibitor may include a dose of immunoregulatory peptide inhibitorsufficient to at least partially arrest a symptom of immunosuppression(e.g., an amount sufficient to improve proliferation or migration ofimmune cells). In some embodiments, a therapeutically effective amountincludes at least about 1 nanogram of substantially pureimmunoregulatory peptide inhibitor, for example, at least or equal toabout 1 nanogram, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50,60, 70, 80, 90, 100, 120, 140, 160, 180, 200, 250, 300, 350, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000 nanograms, 1microgram, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50, 60, 70,80, 90, 100, 120, 140, 160, 180, 200, 250, 300, 350, 400, 450, 500, 550,600, 650, 700, 750, 800, 850, 900, 950, 1000 micrograms, about 1milligram, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50, 60, 70,80, 90, 100, 120, 140, 160, 180, 200, 250, 300, 350, 400, 450, 500, 550,600, 650, 700, 750, 800, 850, 900, 950, 1000 milligrams, or 1.1 gram,1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2, 3, 3.5, 4, 4.5, 5, 5.5, 6,6.5, 7, 7.5, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 55, 60, 65, 70, 75, 80, 85, 90,95, 99, 100, 105, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 250,300, 350, 400, 450, or 500 grams, including ranges between any two ofthe listed values can be provided to a patient in need.

In some embodiments, a therapeutically effective amount can be providedaccording to a schedule that includes one, or more than oneadministration of a therapeutically effective amount of inhibitor, forexample at least or equal to about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,48, 49, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99, 100, 105, 110, 120,130, 140, 150, 160, 170, 180, 190, 200, 250, 300, 350, 400, 450, or 500administrations. An administration can be provided hourly or less, forexample no more than once every 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 hours, or no more thanonce every 1 day, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5,8, 9, 10, 11, 12, 13, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,27, 28, 29, 30, or 31 days.

By some methods, after administration of the immunoregulatory peptideinhibitor, a reduction in immunosuppression is measured, detected, orobserved. In some embodiments, a reduction in immunosuppression isdetected, measured, or observed by obtaining a biological sample fromthe patient that received the immunoregulatory peptide inhibitor anddetecting a reduction in immune cell receptor binding to P3028 and/or adetecting immune cell proliferation after IL-2 induction of the immunecells present in the biological sample. In some embodiments, theanalysis of the biological sample obtained from the patient above iscompared to the same analysis (e.g., determining the amount of immunecell receptor binding to the P3028 sequence/structure or IL-2 inducedimmune cell proliferation) conducted on a control biological sample, forexample, a biological sample from the same patient taken prior toadministration of the immunoregulatory peptide inhibitor or a biologicalsample taken from a healthy human. Examples 9 and 13 describe detectionof a reduction of immunosuppression in cells contacted by serum ascompared to a control sample.

As mentioned above, a reduction in immunosuppression can be detected asan increase in immune cell stimulation, for example immune cellproliferation or immune cell cytotoxicity. A reduction in P3028-inducedimmunosuppression, which can be measured in the methods described supra,can include: increased T-Cell receptor stimulation (see Example 3);increased NK-Cell cytotoxicity (see Example 4); increased leukocytespreading (see Example 5); increased immune cell migration (see Example5); and/or IL-2 Induced Proliferation (see Example 6). Decreased IL-6production can also an improvided prognosis for cancer patients, forexample cancer patients suffering from immunosuppression (see U.S. Pat.No. 8,110,347, herein expressly incorporated by reference in itsentirety). Desirably, a reduction in immunosuppression is detected by anincreased proliferative response of PBMC's to IL-2, as shown in Example9, or by detecting activation or stimulation of an immune cell, asevidenced by an increase in CD69 or CD71 expression, induction of thesecretion of a signal substance, as evidenced by interferon gamma orIL-12 production, or stimulation of the release of a cytolyticsubstance, as evidenced by the release of granzyme B or perforin,enhanced cytotoxicity, cytokine production, cell migration, and/or cellproliferation.

In some embodiments, the reduction in immunosuppression is detected bydetecting the presence or quantity of markers from immune cells and/orserum and/or albumin collected from a patient. In some embodiments, thedetection includes collecting patient serum, blood, and/or patientalbumin, and contacting the patient serum, plasma, blood, or albuminwith an immune cell ex vivo. In some embodiments, the immune cell isalso contacted with IL-2. The proliferative response of the immune cellto IL-2 can be used to detect a decrease in immunosuppression. Theimmune cell can be a patient cell, or a cell from another human, or acell from cell culture. In some embodiments, the reduction inimmunosuppression can be detected by detecting effects of increasedimmune system activity, for example reduction in cancer cell number, areduction in tumor size, or a reduction or inhibition of cancer cellproliferation. In some embodiments, cancer cells can be identified, andcancer cells can thus be quantified, by detecting cells that bind to theP3028 sequence/structure (see Example 7) or an inhibitor of the P3028sequence/structure (see Example 14).

Methods of Inhibiting Binding of an Albumin Fragment to a Receptor

Additional methods include approaches for inhibiting the binding of analbumin fragment to an immune cell receptor (e.g., an LFA-1 and/or anIL-2 receptor). The method can include identifying a human sufferingfrom immunosuppression, as described herein. The immunosuppression canbe caused by one or more immunoregulatory peptide or structure.Exemplary immunoregulatory peptides or structures include P3028sequence/structures, and/or proteins or peptides that comprise, consistof, or consist essentially of the sequences of SEQ ID NOs: 183-185 or188-246. The method can also include contacting an immune cell with apeptide that comprises, consists of, or consists essentially of apeptide inhibitor as described herein. For example, the peptide used inthese methods can comprise, consist of, or consist essentially ofFormula (I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166) as described herein. In someembodiments, X is an optional sequence, and can be KKLDT (SEQ ID NO:167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO:170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO:253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO:256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO:172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO:261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ,EDT, EDQ, DT, DQ, T, or Q, or absent. In some embodiments, X₁ is one ofFF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, orVL. In some embodiments, X₂ is one of LS, LQ, LM, LT, LH, VS, VQ, VM,VT, or VH. In some embodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR. In some embodiments, X₄ is an optional sequence,and can be ER, or E, or absent. In some embodiments, if X is absent, X₁is FF, and X₂ is LS. In some embodiments, the isolated peptides thatcomprise Formula (I) used in these methods have a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide used in these methods can comprise, consistof, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂ (SEQ ID NO:173), In some embodiments, X₂₀ is an optional sequence, and can be KKLD(SEQ ID NO: 174), RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO: 176), KKED(SEQ ID NO: 177), KLD, LD, or D, or absent. X₂₁ is an optional sequence,and can be LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT,QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT,VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT,LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN,QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN,VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP,LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP,QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP,MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR,LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR,QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR,VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR, or absent. Insome embodiments, X₂₂ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, the isolated peptides that comprise Formula(II) used in these methods have a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values.

Additionally, the peptide used in these methods can comprise, consistof, or consist essentially of Formula (III), X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQID NO: 178). In some embodiments, X₃₀ is an optional sequence, and canbe KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO: 180), LDTF (SEQ ID NO:181), DTF, TF, or F, or absent. In some embodiments, X₃₁ is an optionalsequence, and can be F, S, M, V, T, or L, or absent. In someembodiments, X₃₁ is F. In some embodiments, X₃₂ can be S, Q, M, T, or H.In some embodiments, X₃₂ is S. X₃₃ can be F, M, Q, H, N, P, S, G, A, orR. In some embodiments, X₃₄ is F. X₃₄ is an optional sequence, and canbe R or absent. In some embodiments, the isolated peptides that compriseFormula (III) used in these methods have a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide used in these methods can comprise, consistof, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide used in these methods can comprise, consistof, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂E X₈₀₃(SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ is anoptional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R, T,V, or K, or absent. In some embodiments, X₈₀₁ is an optional sequence,and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597), EDTFFV (SEQID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO: 600), LDTVFV(SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ ID NO: 603),LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQ ID NO:606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK (SEQ IDNO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611), DDTFFV (SEQID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO: 614), IDTFFV(SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ ID NO: 617),NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQ ID NO:620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV (SEQ IDNO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625), LITFFV (SEQID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO: 628), LYTFFV(SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ ID NO: 631),LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQ ID NO:634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV (SEQ IDNO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639), LDTNFV (SEQID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO: 642), LDTFQV(SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ ID NO: 645),LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQ ID NO:648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV (SEQ IDNO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653), LDTLFV (SEQID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO: 656), LDHFFV(SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ ID NO: 659),LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQ ID NO:662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV (SEQ IDNO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667), LDTFPV (SEQID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO: 670), LDTGFV(SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ ID NO: 673),LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQ ID NO:676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV (SEQ IDNO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681), LDTHFV (SEQID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO: 684), LDLFFV(SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ ID NO: 687),LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQ ID NO:690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV (SEQ IDNO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695), LDTFFQ (SEQID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO: 698), LDKFFV(SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ ID NO: 701),LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQ ID NO:704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN (SEQ IDNO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709), LDTFFD (SEQID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712), TFFV (SEQID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L, or absent.In some embodiments, X₈₀₂ is an optional sequence, and can be LSLFT (SEQID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717), LMLFT (SEQID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720), LSQFT (SEQID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723), LSLMT (SEQID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726), LSLNT (SEQID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729), LSLGT (SEQID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732), LSLFN (SEQID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735), LGLFT (SEQID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738), GSLFT (SEQID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741), NSLFT (SEQID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744), RSLFT (SEQID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747), YSLFT (SEQID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750), LSHFT (SEQID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753), LSRFT (SEQID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756), LSWFT (SEQID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759), LSLLT (SEQID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762), LSLWT (SEQID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765), LSLFH (SEQID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768), LSLFM (SEQID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771), LSLFW (SEQID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774), LSFFT (SEQID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777), LSCFT (SEQID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780), LPLFT (SEQID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783), LDLFT (SEQID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786), WSLFT (SEQID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789), LSPFT (SEQID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792), LILFT (SEQID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795), LSLFY (SEQID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798), LFLFT (SEQID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801), LLLFT (SEQID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804), LSLFE (SEQID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807), LSDFT (SEQID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810), SLFT (SEQID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, or absent. Insome embodiments, X₈₀₃ is an optional sequence, and can be R, F, K, N,R, T, or Y, or absent. In some embodiments, the isolated peptidecomprising Formula (VIII) has a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula(IX). Accordingly, in someembodiments, the peptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in Table 5.1. In some embodiments, the isolatedpeptide from Table 5.1 used in these methods has a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide used in these methods can comprise, consistof, or consist essentially of and/or SEQ ID NOs: 1-33, 34, 46-53, 64-66,68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one or more of thepeptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13, as described herein. In some embodiments, these isolatedpeptides used in these methods have a length that is less than or equalto 1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8,9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44,45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62,63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80,81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98,99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values. The immune cell can be in thepresence of human serum, for example albumin or an albumin fragment asdescribed herein.

Some embodiments of the invention include methods of inhibiting thebinding of a human albumin fragment (e.g., an albumin fragment havingthe P3028 sequence/structure) to an LFA-1 receptor or IL-2 receptor.P3028, an albumin fragment, can bind to the LFA-1 receptor and the IL-2receptor (see Examples 7 and 8) and this binding can be inhibited byproviding a composition that comprises, consists essentially of, orconsists of an immunoregulatory peptide inhibitor. In some embodiments,methods of inhibiting binding of P3028 to the LFA-1 or IL-2 receptorinclude contacting or binding an immunoregulatory peptide inhibitor toP3028 in vivo or in vitro, and, optionally, detecting an inhibition ofbinding of P3028 to an LFA-1 receptor or an IL-2 receptor. Binding ofP3028 to the LFA-1 receptor and IL-2 receptor can be inhibited bybinding P3028 to an antibody that binds specifically to P3028, forexample (see Example 9). These methods can also be practiced by bindinga peptide-based immunoregulatory peptide inhibitor that has the capacityto remove or inhibit P3028's blockage of the LFA-1 receptor, for examplethe P28R immunoregulatory peptide inhibitor (SEQ ID NO: 2) (see Example16) or the P28 core peptide (SEQ ID NO: 62) (see Example 38).

Preferably, the composition that comprises, consists of, or consistsessentially of an immunoregulatory peptide inhibitor used in thesemethods includes an immunoregulatory peptide inhibitor that comprises,consists of, or consists essentially of the Formula (I), XX₁VKX₂X₃X₄(SEQ ID NO: 166), as described herein. In some embodiments, X is anoptional sequence, and can be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO:168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO:171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO:254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO:257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO:259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO:262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, orQ, or absent. In some embodiments, X₁ is one of FF, FM, FS, FV, FT, FL,AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, or VL. In some embodiments,X₂ is one of LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH. X₃ can be one ofLFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT,QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT,VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN,LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN,QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN,MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP,LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP,QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP,MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR,LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR,QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR,MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR. In some embodiments, X₄is an optional sequence, and can be ER, or E, or absent. In someembodiments, if X is absent, X₁ is FF, and X₂ is LS. In someembodiments, the isolated peptides that comprise Formula (I) used inthese methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173), as described herein. In some embodiments, X₂₀ is anoptional sequence, and can be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO:175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO: 177), KLD, LD, or D, orabsent. X₂₁ is an optional sequence, and can be LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR, or absent. In some embodiments, X₂₂ is anoptional sequence, and can be ER, or E, or absent. In some embodiments,the isolated peptides that comprise Formula (II) used in these methodshave a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178), as described herein. In someembodiments, X₃₀ is an optional sequence, and can be KKLDTF (SEQ ID NO:179), KLDTF (SEQ ID NO: 180), LDTF (SEQ ID NO: 181), DTF, TF, or F, orabsent. In some embodiments, X₃₁ is an optional sequence, and can be F,S, M, V, T, or L, or absent. In some embodiments, X₃₁ is F. In someembodiments, X₃₂ can be S, Q, M, T, or H. In some embodiments, X₃₂ is S.X₃₃ can be F, M, Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ isF. X₃₄ is an optional sequence, and can be R, or absent. In someembodiments, the isolated peptides that comprise Formula (III) used inthese methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, Y, or absent. In some embodiments, the isolated peptidecomprising Formula (VIII) has a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula(IX). Accordingly, in someembodiments, the peptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of and/or SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 as described herein. In some embodiments, theseisolated peptides used in these methods have a length that is less thanor equal to 1100 amino acids, for example, less than or equal to 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96,97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125,126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139,140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270,280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700,750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in Table 5.1. In some embodiments, the isolatedpeptide from Table 5.1 used in these methods has a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values. Additionally, a nucleicacid encoding such a peptide inhibitor can be provided, for example, anucleic acid of SEQ ID NOs: 102-165.

Preferably, the immunoregulatory peptide inhibitor used in theaforementioned methods is P28R, a derivative thereof, or a nucleic acidencoding such a molecule (e.g., any one or more of the immunoregulatorypeptide inhibitors provided SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68, 76,94-96, 98, 264-393, 583-586, or 589 or any one or more of the peptidesprovided in Table 5.1, 5.4, 5.5, 5.6, or any variation or combination ofvariations of P28R or P28 core as provided in Tables 5.3 and 13, or anucleic acid encoding such a molecule. The immunoregulatory peptideinhibitors used in the aforementioned methods can comprise at least oneD amino acid, at least one non-natural amino acid, an N-terminal acetylgroup, or a C terminal amide group and said immunoregulatory peptideinhibitors can be glycosylated, nitrosylated, carbonylated, oxidized, orjoined to a linked pharmacokinetic modifier, PEG, a cytotoxin, orradionuclide.

Some embodiments include removing a bound ligand of the LFA-1 receptoror the IL-2 receptor from the receptor (e.g., a molecule comprisingP3028). As shown in Example 15, binding of an inhibitor of P3028sequence/structure to P3028 can increase the availability of the LFA-1receptor to an antibody that specifically binds the LFA-1 receptor, whencompared to a control sample in which the inhibitor was not bound toP3028. In some embodiments, P3028 is bound to the inhibitor, thusremoving the binding of P3028 from the IL-2 receptor (see Examples 9 and13).

Methods of Binding Cancer Cells with an Immunoregulatory PeptideInhibitor

Embodiments also include methods of binding cancer cells with animmunoregulatory peptide inhibitor (e.g., an immunoregulatory peptideinhibitor having a cytotoxin, radionuclide, or detectable label). Thesemethods are practiced by contacting cancer cells (e.g., in vitro or invivo) with a composition that comprises, consists of, or consistsessentially of any one or more of the immunoregulatory peptideinhibitors described herein. For example, the peptide inhibitor used inthese methods can comprise, consist of, or consist essentially ofFormula (I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166) as described herein. In someembodiments, X is an optional sequence, and can be KKLDT (SEQ ID NO:167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO:170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO:253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO:256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO:172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO:261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ,EDT, EDQ, DT, DQ, T, or Q, or absent. In some embodiments, X₁ is one ofFF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, orVL. In some embodiments, X₂ is one of LS, LQ, LM, LT, LH, VS, VQ, VM,VT, or VH. In some embodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR. In some embodiments, X₄ is an optional sequence,and can be ER, or E, or absent. In some embodiments, if X is absent, X₁is FF, and X₂ is LS. In some embodiments, the isolated peptides thatcomprise Formula (I) used in these methods have a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173). In some embodiments, X₂₀ is an optional sequence, andcan be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO:176), KKED (SEQ ID NO: 177), KLD, LD, D, or absent. X₂₁ is an optionalsequence, and can be LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT,QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT,VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT,MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN,QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN,VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN,LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP,QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP,VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO:815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR,QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR,VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR, orabsent. In some embodiments, X₂₂ is an optional sequence, and can be ER,or E, or absent. In some embodiments, the isolated peptides thatcomprise Formula (II) used in these methods have a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. In some embodiments, theisolated peptides that comprise Formula (III) used in these methods havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula(VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of and/or SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 as described herein. In some embodiments, theseisolated peptides used in these methods have a length that is less thanor equal to 1100 amino acids, for example, less than or equal to 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96,97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125,126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139,140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270,280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700,750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in Table 5.1. In some embodiments, the isolatedpeptide from Table 5.1 used in these methods has a length that is lessthan or equal to 1100 amino acids, for example, less than or equal to 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110,111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124,125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650,700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values. Additionally, a nucleicacid encoding such a peptide inhibitor can be provided, for example anucleic acid of SEQ ID NOs: 102-165.

Preferably, the immunoregulatory peptide inhibitor used in theaforementioned methods is P28R, P28 core, a derivative thereof, or anucleic acid encoding such a molecule (e.g., any one or more of theimmunoregulatory peptide inhibitors provided by SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13, or a nucleic acid encoding such a molecule (e.g.,SEQ ID NOs: 102-165)). The immunoregulatory peptide inhibitors used inthe aforementioned methods can comprise at least one D amino acid, atleast one non-natural amino acid, an N-terminal acetyl group, or a Cterminal amide group and said immunoregulatory peptide inhibitors can beglycosylated or joined to PEG, a cytotoxin, or radionuclide.

Once the immunoregulatory peptide inhibitor or antibody that bindsspecifically to any immunoregulatory peptide of Tables 1-4 is bound tothe cancer cell, it can be detected. That is, optionally, the methodabove includes a detecting step whereby the binding of theimmunoregulatory peptide inhibitor is determined directly or indirectly.In some embodiments, the binding of the immunoregulatory peptideinhibitor is directly detected as in Example 14. In some embodiments,the binding of the immunoregulatory peptide inhibitor is indirectlydetected. As described herein, the presence of P3028 on cancer cells canlocally suppress an immune response. Thus, in some embodiments,detecting the binding of an immunoregulatory peptide inhibitor to acancer cell can also include a step of detecting a reversal ofimmunosuppression, as described in Example 13. Reversal ofimmunosuppression can be determined, for example as a reversal ofimpaired PBMC proliferation (see Examples 2 and 13), reversal of T cellreceptor stimulation (see Example 3), reversal of decreased NK cellcytotoxicity (see Example 4), reversal of decreased leukocyte spreading(see Example 5) or decreased immune cell migration (see Example 6), orincreased IL-2 induced proliferation (see Examples 6 and 9). In someembodiments, cancer cells are bound to an immunoregulatory peptideinhibitor in vivo. Example 16 describes delivery of an inhibitor ofP3028 to cancer cells in vivo. Example 42 describes detection of aninhibitor of P3028 on cancer cells.

In some embodiments, the detection of an immunoregulatory peptideinhibitor can occur on tissue biopsies obtained from a human. In someembodiments, the tissue biopsies can include putative cancer cells, orthe biopsies can be screened for cancer cells. By these methods, thetissue biopsies are contacted with an immunoregulatory peptideinhibitor, as described herein. Preferably, the immunoregulatory peptideinhibitor comprises a detectable label, as described herein. In someembodiments, live cells are contacted with the immunoregulatory peptideinhibitor (see Example 14). In some embodiments, histological sectionsare bound with the immunoregulatory peptide inhibitor. The detectablelabel is then detected, thus permitting identification of cancer cellswhich cannot be attacked by the immune system. The detectable label canbe detected through methods known in the art, for example byimmunoassays, a blotting technique, ELISA, ELISpot, flow cytometry,cytometric bead assay, proteomics, and/or immunohistochemistry.

Methods of Delivering a Cytotoxin or Radionuclide to a Cancer Cell

Additional embodiments include methods of delivering a cytotoxin orradionuclide to a cancer cell. Some embodiments include targeting aradioactive substance (e.g., ¹¹¹I, ¹³¹I, ⁹⁰Y, ⁶⁷CU, ¹⁸⁶Re, ¹⁸⁸Re, ²¹²Bior ²¹¹At) or a therapeutic compound (e.g., a toxin) to a cancer cell. Asdescribed herein, immunoregulatory peptide inhibitors, for examplepeptide P28R, bind to cancer cells, but not to healthy immune cells, forexample lymphocytes (see Example 14). Thus in some embodiments, bindingof a therapeutic compound to a cancer cell can be mediated by theimmunoregulatory peptide inhibitor. In some embodiments, a therapeuticcompound, for example a cytoxin, a radiotoxin, or the like as describedherein is attached to the immunoregulatory peptide inhibitor that bindsto P3028.

These methods are practiced by contacting cancer cells (e.g., in vitroor in vivo) with a composition that comprises, consists of, or consistsessentially of any one or more of the immunoregulatory peptideinhibitors described herein, which comprises a radioactive substance(e.g., ¹¹¹I, ¹³¹I, ⁹⁰Y, ⁶⁷Cu, ¹⁸⁶Re, ¹⁸⁸Re, ²¹²Bi or ²¹¹At) or atherapeutic compound (e.g., a toxin). In some embodiments, theimmunoregulatory peptide inhibitor used in these methods comprises,consists of or consists essentially of a peptide as described herein.For example, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (I), XX₁VKX₂X₃X₄ (SEQ IDNO: 166) as described herein. In some embodiments, X is an optionalsequence, and can be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO: 168),KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO: 171),KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO: 254),RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO: 257),RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO: 259),KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO: 262),KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, or Q, orabsent. In some embodiments, X₁ is one of FF, FM, FS, FV, FT, FL, AF,AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, or VL. In some embodiments, X₂is one of LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH. In someembodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT,LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT,VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST,MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN,QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN,VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN,MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP,QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP,VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ IDNO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR,QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR,VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR.In some embodiments, X₄ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, if X is absent, X₁ is FF, and X₂ is LS. Insome embodiments, the isolated peptides that comprise Formula (I) usedin these methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173), as described herein. In some embodiments, X₂₀ is anoptional sequence, and can be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO:175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO: 177), KLD, LD, D, orabsent. X₂₁ is an optional sequence, and can be LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR, or absent. In some embodiments, X₂₂ is anoptional sequence, and can be ER, or E, or absent. In some embodiments,the isolated peptides that comprise Formula (II) used in these methodshave a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. In some embodiments, theisolated peptides that comprise Formula (III) used in these methods havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (IX). Accordingly, in someembodiments, the peptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of and/or SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 as describedherein. In some embodiments, these isolated peptides used in thesemethods have a length that is less than or equal to 1100 amino acids,for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68,69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86,87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103,104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117,118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131,132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190,200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360,380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000,1050, or 1100 amino acids, including ranges between any two of thelisted values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in or any one or more of the peptides provided inTable 5.1, 5.4, 5.5, 5.6, or any variation or combination of variationsof P28R or P28 core as provided in Tables 5.3 and 13. In someembodiments, the isolated peptide from or any one or more of thepeptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13 used in these methods has a length that is less than or equal to1100 amino acids, for example, less than or equal to 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290,300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800,850, 900, 950, 1000, 1050, or 1100 amino acids, including ranges betweenany two of the listed values.

Preferably, the immunoregulatory peptide inhibitor used in theaforementioned methods is P28R, a derivative thereof, or a nucleic acidencoding such a molecule (e.g., any one or more of the immunoregulatorypeptide inhibitors provided by SEQ ID NOs: 1-33, 34, 46-53, 64-66, 68,76, 94-96 or 98 or any one or more of the peptides provided in Table5.1). The immunoregulatory peptide inhibitors used in the aforementionedmethods can comprise at least one D amino acid, at least one non-naturalamino acid, an N-terminal acetyl group, or a C terminal amide group andsaid immunoregulatory peptide inhibitors can be glycosylated or joinedto PEG.

Once the immunoregulatory peptide inhibitor comprising the cytotoxin orradionuclide has contacted the cancer cell, (e.g., in a human patient)the toxin and/or radionuclide can induce cancer cell death. In someembodiments, the cancer cell death comprises apoptosis. Optionally, celldeath can comprise Caspase 3 activation (see Example 39). In someembodiments, peptide P28R (SEQ ID NO: 2) or a pharmaceutical compositioncomprising or consisting essentially of P28R is administeredperi-tumorally or near a tumor (for example within 10 cm, 9 cm, 8 cm, 7cm, 6 cm, 5 cm, 4 cm, 3 cm, 2 cm, 1 cm, or 0.5 cm of the tumor), andinduces cell death of tumor cells. In some embodiments, the tumorcomprises prostate cancer cells. In some embodiments, the tumorcomprises a melanoma, for example a B16 melanoma. In some embodiments,at least about 10 ng/100 ml of peptide inhibitor are administeredperi-tumorally, for example about 10 ng/100 ml, 20 ng/100 ml, 30 ng/100ml, 40 ng/100 ml, 50 ng/100 ml, 60 ng/100 ml, 70 ng/100 ml, 80 ng/100ml, 90 ng/100 ml, 100 ng/100 ml, 200 ng/100 ml, 300 ng/100 ml, 400ng/100 ml, 500 ng/100 ml, 600 ng/100 ml, 700 ng/100 ml, 800 ng/100 ml,900 ng/100 ml, 1 μg/100 ml, 2 μg/100 ml, 3 μg/100 ml, 4 μg/100 ml, 5μg/100 ml, 6 μg/100 ml, 7 μg/100 ml, 8 μg/100 ml, 9 μg/100 ml, 10 μg/100ml 20 μg/100 ml, 30 μg/100 ml, 40 μg/100 ml, 50 μg/100 ml, 100 μg/100ml, 200 μg/100 ml, 500 μg/100 ml, 1000 μg/100 ml, including rangesbetween any two of the listed values, for example about 10 ng-100 ng/100ml, 10 ng-200 ng/100 ml, 10 ng-500 ng/100 ml, 10 ng-1 μg/100 ml, 20ng-10 μg/100 ml, 100 ng-200 ng/100 ml, 100 ng-500 ng/100 ml, 100 ng-1μg/100 ml, 200 ng-10 μg/100 ml, 200 ng-500 ng/100 ml, 200 ng-1 μg/100ml, 200 ng-10 μg/100 ml, 1 μg-100 μg/100 ml, 1 μg-500 μg/100 ml, about 1μg-1000 μg/100 ml, 5 μg-100 μg/100 ml, 5 μg-500 μg/100 ml, 5 μg-1000μg/100 ml, 10 μg-100 μg/100 ml, 10 μg-500 μg/100 ml, 10 μg-1000 μg/100ml, 50 μg-100 μg/100 ml, 50 μg-500 μg/100 ml, 50 μg-1000 μg/100 ml, 100μg-500 μg/100 ml, or about 100 μg-1000 μg/100 ml. In some embodiments,the pharmaceutical composition is administered systemically. In someembodiments, the pharmaceutical composition is administered inconjunction with a second therapeutic agent, for example a therapeuticagent selected to stimulate an immune cell after an LFA-1 receptor ofthe immune cell has been de-blocked (e.g. bound immunoregulatorypeptides or 3028 structures have been displaced from the LFA-1receptor).

Optionally, these methods include the steps of observing or monitoringthe cancer or progression of the cancer of the patient. In someembodiments, the immunoregulatory peptide inhibitor comprising thecytotoxin or radionuclide is administered to a cancer patient havingcolorectal cancer, renal cancer, breast cancer, skin cancer, ovariancancer, prostate cancer, pancreatic cancer, lung cancer, malignantmelanoma, small cell lung cancer, non-small lung cancer(adenocarcinoma), squamous cell carcinoma, bladder cancer, osteosarcoma,bronchial cancer, or hematopoietic cell cancer. In some embodiments, abiological sample of a human is screened for binding of immunoregulatorypeptide inhibitor prior to administering the immunoregulatory peptideinhibitor comprising the cytotoxin or radionuclide. For, example, animmunoregulatory peptide inhibitor or antibody that binds specificallyto an immunoregulatory peptide of any one of Tables 1-4 bound to adetectable label can be administered to a biological sample as inExample 14 or Example 41. From detection of the detectable label, it canbe confirmed that cancer cells are bound by immunoregulatory peptideinhibitor, and then the same immunoregulatory peptide inhibitorcomprising the cytotoxin or radionuclide can be provided to the patient.

Methods of Inhibiting the Proliferation of Cancer Cells

Some embodiments of the invention include methods of inhibiting theproliferation of cancer cells. The method can include identifying ahuman cancer patient. The patient can be suffering from one or morecancers, for example colorectal cancer, renal cancer, breast cancer,skin cancer, ovarian cancer, prostate cancer, pancreatic cancer, lungcancer, malignant melanoma, small cell lung cancer, non-small lungcancer (adenocarcinoma), squamous cell carcinoma, bladder cancer,osteosarcoma, bronchial cancer, or hematopoietic cell cancer. The methodcan include contacting immune cells of the human by an immunoregulatorypeptide inhibitor. In some embodiments, contacting the immune cellscomprises intra-tumoral administration, or administration near a tumor,for example within 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.5 cm of thetumor. In some embodiments, the immunoregulatory peptide inhibitorcomprises, consists of or consists essentially of a peptide as describedherein. For example, the peptide inhibitor used in these methods cancomprise, consist of, or consist essentially of Formula (I), XX₁VKX₂X₃X₄(SEQ ID NO: 166) as described herein. In some embodiments, X is anoptional sequence, and can be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO:168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO:171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO:254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO:257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO:259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO:262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, orQ, or absent. In some embodiments, X₁ is one of FF, FM, FS, FV, FT, FL,AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, or VL. In some embodiments,X₂ is one of LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH. In someembodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT,LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT,VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST,MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN,QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN,VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN,MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP,QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP,VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ IDNO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR,QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR,VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR.In some embodiments, X₄ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, if X is absent, X₁ is FF, and X₂ is LS. Insome embodiments, the isolated peptides that comprise Formula (I) usedin these methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173), as described herein. In some embodiments, X₂₀ is anoptional sequence, and can be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO:175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO: 177), KLD, LD, or D, orabsent. X₂₁ is an optional sequence, and can be LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR, or absent. In some embodiments, X₂₂ is anoptional sequence, and can be ER, E, or absent. In some embodiments, theisolated peptides that comprise Formula (II) used in these methods havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. In some embodiments, theisolated peptides that comprise Formula (III) used in these methods havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula(IX). Accordingly, in someembodiments, the peptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of and/or SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 as described herein. In some embodiments, theseisolated peptides have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in Table 5.1, 5.4, 5.5, 5.6, or any variation orcombination of variations of P28R or P28 core as provided in Tables 5.3and 13. In some embodiments, the isolated peptide from Table 5.1 used inthese methods has a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

In some embodiments, the method includes providing to the human apolynucleotide encoding such a peptide inhibitor (e.g., any one or moreof the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or any variationor combination of variations of P28R or P28 core as provided in Tables5.3 and 13). For example, a polynucleotide encoding such a peptideinhibitor can be provided, for example a nucleic acid of SEQ ID NOs:102-165.

Reduction of cancer-associated immunosuppression can induce and/orenhance an immune response against cancer cells. An immune responseagainst cancer cells can reduce cancer cell proliferation, and/or causecancer cells to undergo cell death or apoptosis. Thus, the method caninclude detecting an inhibition in the proliferation of cancer cells ofthe patient. The method can include detecting an induction of cell deathor apoptosis of cancer cells of the patient. The method can includedetecting an inhibition in the proliferation of cancer cells of thepatient, and an induction of cell death or apoptosis of cancer cells ofthe patient. Apoptosis can be identified as known in the art, forexample by neutral red assay, by trypan blue exclusion of dead cells, byacridine orange staining, by TUNEL staining, and/or by detection ofcleaved PARP, and/or cleaved caspases.

Methods of Removing Ligands Bound to the LFA-1 Receptor

Some embodiments of the invention include methods of removing a ligandbound to the LFA-1 receptor of human lymphocytes. The methods caninclude contacting human lymphocytes with an immunoregulatory peptideinhibitor, or a polynucleotide encoding such an inhibitor. In someembodiments, the immunoregulatory peptide inhibitor comprises, consistsof or consists essentially of a peptide as described herein. Forexample, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (I), XX₁VKX₂X₃X₄ (SEQ IDNO: 166) as described herein. In some embodiments, X is an optionalsequence, and can be KKLDT (SEQ ID NO: 167), RKLDT (SEQ ID NO: 168),KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO: 170), KKLDQ (SEQ ID NO: 171),KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO: 253), RKLDQ (SEQ ID NO: 254),RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO: 256), RKGTD (SEQ ID NO: 257),RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO: 172), KGDT (SEQ ID NO: 259),KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO: 261), KGDQ (SEQ ID NO: 262),KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ, EDT, EDQ, DT, DQ, T, or Q, orabsent. In some embodiments, X₁ is one of FF, FM, FS, FV, FT, FL, AF,AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, or VL. In some embodiments, X₂is one of LS, LQ, LM, LT, LH, VS, VQ, VM, VT, or VH. In someembodiments, X₃ is one of LFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT,LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT,VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST,MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN,QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN,VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN,MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP,QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP,VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ IDNO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR,QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR,VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR.In some embodiments, X₄ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, if X is absent, X₁ is FF, and X₂ is LS. Insome embodiments, the isolated peptides that comprise Formula (I) usedin these methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂(SEQ ID NO: 173), as described herein. In some embodiments, X₂₀ is anoptional sequence, and can be KKLD (SEQ ID NO: 174), RKLD (SEQ ID NO:175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO: 177), KLD, LD, or D, orabsent. X₂₁ is an optional sequence, and can be LFT, LMT, LQT, LHT, LNT,LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT, QAT,QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT, MQT,MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN, LSN,LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN, VFN,VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN, MNN,MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP, LAP,LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP, VQP,VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP, MSP,MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR, LGR,LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR, VMR,VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR, MPR,MSR, MGR, MAR, or MRR, or absent. In some embodiments, X₂₂ is anoptional sequence, and can be ER, E, or absent. In some embodiments, theisolated peptides that comprise Formula (II) used in these methods havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (III),X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). In some embodiments, X₃₀ is anoptional sequence, and can be KKLDTF (SEQ ID NO: 179), KLDTF (SEQ ID NO:180), LDTF (SEQ ID NO: 181), DTF, TF, or F, or absent. In someembodiments, X₃₁ is an optional sequence, and can be F, S, M, V, T, orL, or absent. In some embodiments, X₃₁ is F. In some embodiments, X₃₂can be S, Q, M, T, or H. In some embodiments, X₃₂ is S. X₃₃ can be F, M,Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ is F. X₃₄ is anoptional sequence, and can be R or absent. In some embodiments, theisolated peptides that comprise Formula (III) used in these methods havea length that is less than or equal to 1100 amino acids, for example,less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133,134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400,450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or1100 amino acids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈ X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), asdescribed herein. In some embodiments, X₇₀₀ is an optional sequence, andcan be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, or V, or absent. Insome embodiments, X₇₀₁ is an optional sequence, and can be L, A, C, D,E, F, G, H, I, K, M, N, Q, R, S, T, or V, or absent. In someembodiments, X₇₀₂ is an optional sequence, and can be D, A, E, I, V, W,or Y, or absent. In some embodiments, X₇₀₃ is an optional sequence, andcan be T, C, M, N, P, Q, R, S, W, or Y, or absent. In some embodiments,X₇₀₄ is an optional sequence, and can be F, A, I, M, N, P, T, or V, orabsent. In some embodiments, X₇₀₅ is an optional sequence, and can be F,L, M, Q, S, T, or V, or absent. In some embodiments, X₇₀₆ is an optionalsequence, and can be V, F, G, L, P, or R, or absent. In someembodiments, X₇₀₇ is an optional sequence, and can be L, A, F, G, I, M,N, P, Q, R, S, T, V, or Y, or absent. In some embodiments, X₇₀₈ is anoptional sequence, and can be S, H, M, N, Q, or T, or absent. In someembodiments, X₇₀₉ is an optional sequence, and can be L, A, H, I, M, N,Q, R, S, T, V, or W, or absent. In some embodiments, X₇₁₀ is an optionalsequence, and can be F, A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W,or absent. In some embodiments, X₇₁₁ is an optional sequence, and can beT, F, G, H, I, L, M, N, P, S, V, or W, or absent. In some embodiments,X₇₁₂ is an optional sequence, and can be R, F, K, N, R, T, or Y, orabsent. In some embodiments, the isolated peptide comprising Formula(VII) has a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂EX₈₀₃ (SEQ ID NO: 395), as described herein. In some embodiments, X₈₀₀ isan optional sequence, and can be K, A, D, E, G, H, I, L, M, N, P, Q, R,T, V, or K, or absent. In some embodiments, X₈₀₁ is an optionalsequence, and can be LDTFFV (SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597),EDTFFV (SEQ ID NO: 598), LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO:600), LDTVFV (SEQ ID NO: 601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ IDNO: 603), LDTFVV (SEQ ID NO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQID NO: 606), LDGFFV (SEQ ID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK(SEQ ID NO: 609), ADTFFV (SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611),DDTFFV (SEQ ID NO: 612), FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO:614), IDTFFV (SEQ ID NO: 615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ IDNO: 617), NDTFFV (SEQ ID NO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQID NO: 620), SDTFFV (SEQ ID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV(SEQ ID NO: 623), LATFFV (SEQ ID NO: 624), LETFFV (SEQ ID NO: 625),LITFFV (SEQ ID NO: 626), LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO:628), LYTFFV (SEQ ID NO: 629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ IDNO: 631), LDNFFV (SEQ ID NO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQID NO: 634), LDSFFV (SEQ ID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV(SEQ ID NO: 637), LDTIFV (SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639),LDTNFV (SEQ ID NO: 640), LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO:642), LDTFQV (SEQ ID NO: 643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ IDNO: 645), LDTFFL (SEQ ID NO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQID NO: 648), LDTFIV (SEQ ID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV(SEQ ID NO: 651), LDTFCV (SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653),LDTLFV (SEQ ID NO: 654), LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO:656), LDHFFV (SEQ ID NO: 657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ IDNO: 659), LDTFWV (SEQ ID NO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQID NO: 662), LDTFRV (SEQ ID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV(SEQ ID NO: 665), LPTFFV (SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667),LDTFPV (SEQ ID NO: 668), LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO:670), LDTGFV (SEQ ID NO: 671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ IDNO: 673), LCTFFV (SEQ ID NO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQID NO: 676), LDEFFV (SEQ ID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV(SEQ ID NO: 679), LDTCFV (SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681),LDTHFV (SEQ ID NO: 682), LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO:684), LDLFFV (SEQ ID NO: 685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ IDNO: 687), LDTFDV (SEQ ID NO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQID NO: 690), LNTFFV (SEQ ID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV(SEQ ID NO: 693), LDFFFV (SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695),LDTFFQ (SEQ ID NO: 696), LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO:698), LDKFFV (SEQ ID NO: 699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ IDNO: 701), LDTFFW (SEQ ID NO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQID NO: 704), LDTFFH (SEQ ID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN(SEQ ID NO: 707), LDTDFV (SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709),LDTFFD (SEQ ID NO: 710), LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712),TFFV (SEQ ID NO: 713), LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L,or absent. In some embodiments, X₈₀₂ is an optional sequence, and can beLSLFT (SEQ ID NO: 715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717),LMLFT (SEQ ID NO: 718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720),LSQFT (SEQ ID NO: 721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723),LSLMT (SEQ ID NO: 724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726),LSLNT (SEQ ID NO: 727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729),LSLGT (SEQ ID NO: 730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732),LSLFN (SEQ ID NO: 733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735),LGLFT (SEQ ID NO: 736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738),GSLFT (SEQ ID NO: 739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741),NSLFT (SEQ ID NO: 742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744),RSLFT (SEQ ID NO: 745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747),YSLFT (SEQ ID NO: 748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750),LSHFT (SEQ ID NO: 751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753),LSRFT (SEQ ID NO: 754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756),LSWFT (SEQ ID NO: 757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759),LSLLT (SEQ ID NO: 760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762),LSLWT (SEQ ID NO: 763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765),LSLFH (SEQ ID NO: 766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768),LSLFM (SEQ ID NO: 769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771),LSLFW (SEQ ID NO: 772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774),LSFFT (SEQ ID NO: 775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777),LSCFT (SEQ ID NO: 778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780),LPLFT (SEQ ID NO: 781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783),LDLFT (SEQ ID NO: 784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786),WSLFT (SEQ ID NO: 787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789),LSPFT (SEQ ID NO: 790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792),LILFT (SEQ ID NO: 793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795),LSLFY (SEQ ID NO: 796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798),LFLFT (SEQ ID NO: 799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801),LLLFT (SEQ ID NO: 802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804),LSLFE (SEQ ID NO: 805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807),LSDFT (SEQ ID NO: 808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810),SLFT (SEQ ID NO: 811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, orabsent. In some embodiments, X₈₀₃ is an optional sequence, and can be R,F, K, N, R, T, or Y, or absent. In some embodiments, the isolatedpeptide comprising Formula (VIII) has a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of Formula(IX). Accordingly, in someembodiments, the peptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of and/or SEQ ID NOs: 1-33, 34,46-53, 64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one ormore of the peptides provided in Table 5.1, 5.4, 5.5, 5.6, or anyvariation or combination of variations of P28R or P28 core as providedin Tables 5.3 and 13 as described herein. In some embodiments, theseisolated peptides used in these methods have a length that is less thanor equal to 1100 amino acids, for example, less than or equal to 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96,97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125,126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139,140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270,280, 290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700,750, 800, 850, 900, 950, 1000, 1050, or 1100 amino acids, includingranges between any two of the listed values.

Additionally, the peptide inhibitor used in these methods can comprise,consist of, or consist essentially of a peptide inhibitor thatcomprises, consists of, or consists essentially of any one or more ofthe peptides set forth in in Table 5.1, 5.4, 5.5, 5.6, or any variationor combination of variations of P28R or P28 core as provided in Tables5.3 and 13. In some embodiments, the isolated peptide from Table 5.1,5.4, 5.5, 5.6, or any variation or combination of variations of P28R orP28 core as provided in Tables 5.3 and 13 used in these methods has alength that is less than or equal to 1100 amino acids, for example, lessthan or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72,73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120,121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134,135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220,230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450,500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100amino acids, including ranges between any two of the listed values. Insome embodiments, the method includes providing to the human apolynucleotide encoding such a peptide inhibitor. For example, apolynucleotide encoding such a peptide inhibitor can be provided, forexample a nucleic acid of SEQ ID NOs: 102-165.

As shown herein (see Examples 15 and 24; see FIGS. 15, 16, 17 and 26),immunoregulatory peptide inhibitors can bind to immunoregulatory peptidesequences/structures, thus preventing immunoregulatory peptidesequences/structures from binding to the LFA-1 receptor. Exemplaryimmunoregulatory peptides can include P3028 structures/sequences.Exemplary immunoregulatory peptides can include peptides of SEQ ID NOS:183-185 or 188-246. Thus, the methods can include detecting a reducedbinding of a ligand for the LFA-1 receptor as described herein. Reducedbinding of a ligand can be detected using an antibody that recognizes atleast one epitope of the LFA-1 receptor that is blocked when a ligand inbound to it, for example the antibody of Example 15 and 23. Reducedbinding of a ligand can be detected using an antibody that bindsspecifically to a ligand of the LFA-1 receptor, for example an antibodythat binds specifically to an immunoregulatory peptide such as P3028sequence/structure and the like (see Example 9).

Methods of Identifying a Patient in Need

It is contemplated herein that different populations of patients canhave different albumin-derived immunoregulatory peptides, and that agiven albumin-derived immunoregulatory peptide can have differenteffects in different individual patients. As shown in Example 30, somecancer patients have immune cells with a high proliferative response toIL-2, while other cancer patients have immune cells with a lowproliferative response to IL-2. As shown in Examples 31 and 32,different populations of patients can respond differently to the sameinhibitor of immunoregulatory peptides. Additionally, a given inhibitorcan modulate the immune system in some patients, but not in otherpatients. Thus, some embodiments of the invention include methods ofidentifying a patient in need. A patient in need can include a patienthaving albumin-derived immunoregulatory peptides bound to at least someof his or her immune cells. A patient in need can include a patient thatis likely to respond to an inhibitor of an immunoregulatory peptide. Insome embodiments, immune cells of a patient can be isolated. Thepresence of immunoregulatory structures on the immune cells can bedetected. The effect of an inhibitor of an immunoregulatory peptide onthe immune cells can be detected. If an immunoregulatory structure ispresent and/or if immune cell function is modulated by the inhibitor,the patient can be classified as a patient in need. Optionally, aneffective dose of the inhibitor can be determined. A therapeuticallyeffective dose of the inhibitor can be administered to the patient inneed.

Some embodiments include methods of detecting the presence ofimmunoregulatory peptides in an in vitro assay. In vitro methods ofdetecting the presence of albumin-derived immunoregulatory peptidesbound to immune cells, immunoregulatory sequences and structures, and invitro methods of detecting the effects of albumin-derivedimmunoregulatory peptides on immune cell activity are provided in U.S.Pat. No. 8,182,983, hereby expressly incorporated by reference in itsentirety herein; U.S. Pat. No. 7,960,126, hereby expressly incorporatedby reference in its entirety herein; U.S. Pat. No. 8,133,688 herebyexpressly incorporated by reference in its entirety herein; U.S. Pat.No. 8,110,347, hereby expressly incorporated by reference in itsentirety herein; and U.S. Pub. No. 2011/0262470, hereby expresslyincorporated by reference in its entirety herein.

Some embodiments include detecting the response of inhibited immunecells to an inhibitor of immunoregulatory peptides. In some embodiments,immune cells are isolated from a patient. In some embodiments, theimmune cells include PBMCs. In some embodiments, the immune cells arecontacted with an inhibitor of immunoregulatory peptides.

In some embodiments, the immune cells are contacted with an inhibitorthat comprises a peptide comprising, consisting of or consistingessentially of at least one peptide of SEQ ID NOs: 1-33, 34, 46-53,64-66, 68, 76, 94-96, 98, 264-393, 583-586, or 589 or any one or more ofthe peptides provided in Table 5.1, 5.4, 5.5, 5.6, 6.1, 6.2, or 12 orany variation or combination of variations of P28R or P28 core asprovided in Tables 5.3 and 13.

In some embodiments, the immune cells are contacted with an inhibitorthat comprises a peptide comprising, consisting of or consistingessentially of Formula (I), XX₁VKX₂X₃X₄ (SEQ ID NO: 166). In someembodiments, X is an optional sequence, and can be KKLDT (SEQ ID NO:167), RKLDT (SEQ ID NO: 168), KKGDT (SEQ ID NO: 169), KKEDT (SEQ ID NO:170), KKLDQ (SEQ ID NO: 171), KKGDQ (SEQ ID NO: 252), KKEDQ (SEQ ID NO:253), RKLDQ (SEQ ID NO: 254), RKGDQ (SEQ ID NO: 255), RKEDQ (SEQ ID NO:256), RKGTD (SEQ ID NO: 257), RKEDT (SEQ ID NO: 258), KLDT (SEQ ID NO:172), KGDT (SEQ ID NO: 259), KEDT (SEQ ID NO: 260), KLDQ (SEQ ID NO:261), KGDQ (SEQ ID NO: 262), KEDQ (SEQ ID NO: 263), LDT, LDQ, GDT, GDQ,EDT, EDQ, DT, DQ, T, or Q, or absent. In some embodiments, X1 is one ofFF, FM, FS, FV, FT, FL, AF, AM, AS, AV, AT, AL, VF, VM, VS, VV, VT, orVL. In some embodiments, X2 can be one of LS, LQ, LM, LT, LH, VS, VQ,VM, VT, or VH. In some embodiments, X3 can be one of LFT, LMT, LQT, LHT,LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT, QNT, QPT, QST, QGT,QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT, VAT, VRT, MFT, MMT,MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN, LQN, LHN, LNN, LPN,LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN, QSN, QGN, QAN, QRN,VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN, MFN, MMN, MQN, MHN,MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP, LNP, LPP, LSP, LGP,LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP, QAP, QRP, VFP, VMP,VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP, MQP, MHP, MNP, MPP,MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR, LHR, LNR, LPR, LSR,LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR, QGR, QAR, QRR, VFR,VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR, MMR, MQR, MHR, MNR,MPR, MSR, MGR, MAR, or MRR. In some embodiments, X₄ is an optionalsequence, and can be ER, or E, or absent. In some embodiments, if X isabsent, X₁ is FF, and X₂ is LS. In some embodiments, the peptidecomprises one of SEQ ID NOs: 2-33. In some embodiments, the isolatedpeptides that comprise Formula (I) have a length that is less than orequal to 1100 amino acids, for example, less than or equal to 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280,290, 300, 320, 340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750,800, 850, 900, 950, 1000, 1050, or 1100 amino acids, including rangesbetween any two of the listed values.

In some embodiments, the immune cells are contacted with an inhibitorthat comprises a peptide comprising, consisting of or consistingessentially of Formula (II), X₂₀TFFVKLSX₂₁X₂₂ (SEQ ID NO: 173). In someembodiments, X₂₀ is an optional sequence, and can be KKLD (SEQ ID NO:174), RKLD (SEQ ID NO: 175), KKGD (SEQ ID NO: 176), KKED (SEQ ID NO:177), KLD, LD, or D, or absent. X₂₁ is an optional sequence, and can beLFT, LMT, LQT, LHT, LNT, LPT, LST, LGT, LAT, LRT, QFT, QMT, QQT, QHT,QNT, QPT, QST, QGT, QAT, QRT, VFT, VMT, VQT, VHT, VNT, VPT, VST, VGT,VAT, VRT, MFT, MMT, MQT, MHT, MNT, MPT, MST, MGT, MAT, MRT, LFN, LMN,LQN, LHN, LNN, LPN, LSN, LGN, LAN, LRN, QFN, QMN, QQN, QHN, QNN, QPN,QSN, QGN, QAN, QRN, VFN, VMN, VQN, VHN, VNN, VPN, VSN, VGN, VAN, VRN,MFN, MMN, MQN, MHN, MNN, MPN, MSN, MGN, MAN, MRN, LFP, LMP, LQP, LHP,LNP, LPP, LSP, LGP, LAP, LRP, QFP, QMP, QQP, QHP, QNP, QPP, QSP, QGP,QAP, QRP, VFP, VMP, VQP, VHP, VNP, VPP, VSP, VGP, VAP, VRP, MFP, MMP,MQP, MHP, MNP, MPP, MSP, MGP, MAP, MRPR (SEQ ID NO: 815), LFR, LMR, LQR,LHR, LNR, LPR, LSR, LGR, LAR, LRR, QFR, QMR, QQR, QHR, QNR, QPR, QSR,QGR, QAR, QRR, VFR, VMR, VQR, VHR, VNR, VPR, VSR, VGR, VAR, VRR, MFR,MMR, MQR, MHR, MNR, MPR, MSR, MGR, MAR, or MRR, or absent. In someembodiments, X₂₂ is an optional sequence, and can be ER, or E, orabsent. In some embodiments, the isolated peptides that comprise Formula(II) have a length that is less than or equal to 1100 amino acids, forexample, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132,133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380,400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050,or 1100 amino acids, including ranges between any two of the listedvalues.

In some embodiments, the immune cells are contacted with an inhibitorthat comprises a peptide comprising, consisting of or consistingessentially of Formula (III), X₃₀X₃₁VKLX₃₂LX₃₃TEX₃₄ (SEQ ID NO: 178). Insome embodiments, X₃₀ is an optional sequence, and can be KKLDTF (SEQ IDNO: 179), KLDTF (SEQ ID NO: 180), LDTF (SEQ ID NO: 181), DTF, TF, or F,or absent. In some embodiments, X₃₁ is an optional sequence, and can beF, S, M, V, T, or L, or absent. In some embodiments, X₃₁ is F. In someembodiments, X₃₂ can be S, Q, M, T, or H. In some embodiments, X₃₂ is S.X₃₃ can be F, M, Q, H, N, P, S, G, A, or R. In some embodiments, X₃₄ isF. X₃₄ is an optional sequence, and can be R, or absent. In someembodiments, the isolated peptides that comprise Formula (III) used inthese methods have a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

In some embodiments, the immune cells are contacted with an inhibitorthat comprises a peptide comprising, consisting of or consistingessentially of Formula (VII), X₇₀₀K X₇₀₁X₇₀₂X₇₀₃ X₇₀₄X₇₀₅X₇₀₆K X₇₀₇ X₇₀₈X₇₀₉ X₇₁₀ X₇₁₁E X₇₁₂ (SEQ ID NO: 394), as described herein. In someembodiments, X₇₀₀ is an optional sequence, and can be K, A, D, E, G, H,I, L, M, N, P, Q, R, T, or V, or absent. In some embodiments, X₇₀₁ is anoptional sequence, and can be L, A, C, D, E, F, G, H, I, K, M, N, Q, R,S, T, or V, or absent. In some embodiments, X₇₀₂ is an optionalsequence, and can be D, A, E, I, V, W, or Y, or absent. In someembodiments, X₇₀₃ is an optional sequence, and can be T, C, M, N, P, Q,R, S, W, or Y, or absent. In some embodiments, X₇₀₄ is an optionalsequence, and can be F, A, I, M, N, P, T, or V, or absent. In someembodiments, X₇₀₅ is an optional sequence, and can be F, L, M, Q, S, T,or V, or absent. In some embodiments, X₇₀₆ is an optional sequence, andcan be V, F, G, L, P, or R, or absent. In some embodiments, X₇₀₇ is anoptional sequence, and can be L, A, F, G, I, M, N, P, Q, R, S, T, V, orY, or absent. In some embodiments, X₇₀₈ is an optional sequence, and canbe S, H, M, N, Q, or T, or absent. In some embodiments, X₇₀₉ is anoptional sequence, and can be L, A, H, I, M, N, Q, R, S, T, V, or W, orabsent. In some embodiments, X₇₁₀ is an optional sequence, and can be F,A, C, G, H, I, L, M, N, P, Q, R, S, T, V, or W, or absent. In someembodiments, X₇₁₁ is an optional sequence, and can be T, F, G, H, I, L,M, N, P, S, V, or W, or absent. In some embodiments, X₇₁₂ is an optionalsequence, and can be R, F, K, N, R, T, or Y, or absent. In someembodiments, the isolated peptide comprising Formula (VII) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

In some embodiments, the immune cells are contacted with an inhibitorthat comprises a peptide comprising, consisting of or consistingessentially of Formula (VIII), X₈₀₀K X₈₀₁K X₈₀₂E X₈₀₃ (SEQ ID NO: 395),as described herein. In some embodiments, X₈₀₀ is an optional sequence,and can be K, A, D, E, G, H, I, L, M, N, P, Q, R, T, V, or K, or absent.In some embodiments, X₈₀₁ is an optional sequence, and can be LDTFFV(SEQ ID NO: 596), GDTFFV (SEQ ID NO: 597), EDTFFV (SEQ ID NO: 598),LDQFFV (SEQ ID NO: 599), LDTAFV (SEQ ID NO: 600), LDTVFV (SEQ ID NO:601), LDTFMV (SEQ ID NO: 602), LDTFSV (SEQ ID NO: 603), LDTFVV (SEQ IDNO: 604), LDTFTV (SEQ ID NO: 605), LDTFLV (SEQ ID NO: 606), LDGFFV (SEQID NO: 607), LDTFGV (SEQ ID NO: 608), LDTFFK (SEQ ID NO: 609), ADTFFV(SEQ ID NO: 610), CDTFFV (SEQ ID NO: 611), DDTFFV (SEQ ID NO: 612),FDTFFV (SEQ ID NO: 613), HDTFFV (SEQ ID NO: 614), IDTFFV (SEQ ID NO:615), KDTFFV (SEQ ID NO: 616), MDTFFV (SEQ ID NO: 617), NDTFFV (SEQ IDNO: 618), QDTFFV (SEQ ID NO: 619), RDTFFV (SEQ ID NO: 620), SDTFFV (SEQID NO: 621), TDTFFV (SEQ ID NO: 622), VDTFFV (SEQ ID NO: 623), LATFFV(SEQ ID NO: 624), LETFFV (SEQ ID NO: 625), LITFFV (SEQ ID NO: 626),LVTFFV (SEQ ID NO: 627), LWTFFV (SEQ ID NO: 628), LYTFFV (SEQ ID NO:629), LDCFFV (SEQ ID NO: 630), LDMFFV (SEQ ID NO: 631), LDNFFV (SEQ IDNO: 632), LDPFFV (SEQ ID NO: 633), LDRFFV (SEQ ID NO: 634), LDSFFV (SEQID NO: 635), LDWFFV (SEQ ID NO: 636), LDYFFV (SEQ ID NO: 637), LDTIFV(SEQ ID NO: 638), LDTMFV (SEQ ID NO: 639), LDTNFV (SEQ ID NO: 640),LDTPFV (SEQ ID NO: 641), LDTTFV (SEQ ID NO: 642), LDTFQV (SEQ ID NO:643), LDTFFF (SEQ ID NO: 644), LDTFFG (SEQ ID NO: 645), LDTFFL (SEQ IDNO: 646), LDTFFP (SEQ ID NO: 647), LDTFFR (SEQ ID NO: 648), LDTFIV (SEQID NO: 649), LDTSFV (SEQ ID NO: 650), LDTFAV (SEQ ID NO: 651), LDTFCV(SEQ ID NO: 652), LDTQFV (SEQ ID NO: 653), LDTLFV (SEQ ID NO: 654),LTTFFV (SEQ ID NO: 655), LDTFFI (SEQ ID NO: 656), LDHFFV (SEQ ID NO:657), LMTFFV (SEQ ID NO: 658), LDTFEV (SEQ ID NO: 659), LDTFWV (SEQ IDNO: 660), LFTFFV (SEQ ID NO: 661), LDVFFV (SEQ ID NO: 662), LDTFRV (SEQID NO: 663), LDTFHV (SEQ ID NO: 664), LDTYFV (SEQ ID NO: 665), LPTFFV(SEQ ID NO: 666), PDTFFV (SEQ ID NO: 667), LDTFPV (SEQ ID NO: 668),LDTFNV (SEQ ID NO: 669), LDTWFV (SEQ ID NO: 670), LDTGFV (SEQ ID NO:671), LDAFFV (SEQ ID NO: 672), LQTFFV (SEQ ID NO: 673), LCTFFV (SEQ IDNO: 674), LSTFFV (SEQ ID NO: 675), YDTFFV (SEQ ID NO: 676), LDEFFV (SEQID NO: 677), WDTFFV (SEQ ID NO: 678), LDTKFV (SEQ ID NO: 679), LDTCFV(SEQ ID NO: 680), LDTFYV (SEQ ID NO: 681), LDTHFV (SEQ ID NO: 682),LHTFFV (SEQ ID NO: 683), LRTFFV (SEQ ID NO: 684), LDLFFV (SEQ ID NO:685), LDTRFV (SEQ ID NO: 686), LLTFFV (SEQ ID NO: 687), LDTFDV (SEQ IDNO: 688), LDTFFA (SEQ ID NO: 689), LDTFFT (SEQ ID NO: 690), LNTFFV (SEQID NO: 691), LDDFFV (SEQ ID NO: 692), LDIFFV (SEQ ID NO: 693), LDFFFV(SEQ ID NO: 694), LKTFFV (SEQ ID NO: 695), LDTFFQ (SEQ ID NO: 696),LGTFFV (SEQ ID NO: 697), LDTFFC (SEQ ID NO: 698), LDKFFV (SEQ ID NO:699), LDTFKV (SEQ ID NO: 700), LDTEFV (SEQ ID NO: 701), LDTFFW (SEQ IDNO: 702), LDTFFM (SEQ ID NO: 703), LDTFFS (SEQ ID NO: 704), LDTFFH (SEQID NO: 705), LDTFFY (SEQ ID NO: 706), LDTFFN (SEQ ID NO: 707), LDTDFV(SEQ ID NO: 708), LDTFFE (SEQ ID NO: 709), LDTFFD (SEQ ID NO: 710),LTFFV (SEQ ID NO: 711), LDTFF (SEQ ID NO: 712), TFFV (SEQ ID NO: 713),LDF, LDTE (SEQ ID NO: 714), FFV, LDV, LV, or L, or absent. In someembodiments, X₈₀₂ is an optional sequence, and can be LSLFT (SEQ ID NO:715), VSLFT (SEQ ID NO: 716), LQLFT (SEQ ID NO: 717), LMLFT (SEQ ID NO:718), LTLFT (SEQ ID NO: 719), LHLFT (SEQ ID NO: 720), LSQFT (SEQ ID NO:721), LSVFT (SEQ ID NO: 722), LSMFT (SEQ ID NO: 723), LSLMT (SEQ ID NO:724), LSLQT (SEQ ID NO: 725), LSLHT (SEQ ID NO: 726), LSLNT (SEQ ID NO:727), LSLPT (SEQ ID NO: 728), LSLST (SEQ ID NO: 729), LSLGT (SEQ ID NO:730), LSLAT (SEQ ID NO: 731), LSLRT (SEQ ID NO: 732), LSLFN (SEQ ID NO:733), LSLFP (SEQ ID NO: 734), LSLFR (SEQ ID NO: 735), LGLFT (SEQ ID NO:736), ASLFT (SEQ ID NO: 737), FSLFT (SEQ ID NO: 738), GSLFT (SEQ ID NO:739), ISLFT (SEQ ID NO: 740), MSLFT (SEQ ID NO: 741), NSLFT (SEQ ID NO:742), PSLFT (SEQ ID NO: 743), QSLFT (SEQ ID NO: 744), RSLFT (SEQ ID NO:745), SSLFT (SEQ ID NO: 746), TSLFT (SEQ ID NO: 747), YSLFT (SEQ ID NO:748), LNLFT (SEQ ID NO: 749), LSAFT (SEQ ID NO: 750), LSHFT (SEQ ID NO:751), LSIFT (SEQ ID NO: 752), LSNFT (SEQ ID NO: 753), LSRFT (SEQ ID NO:754), LSSFT (SEQ ID NO: 755), LSTFT (SEQ ID NO: 756), LSWFT (SEQ ID NO:757), LSLCT (SEQ ID NO: 758), LSLIT (SEQ ID NO: 759), LSLLT (SEQ ID NO:760), LSLTT (SEQ ID NO: 761), LSLVT (SEQ ID NO: 762), LSLWT (SEQ ID NO:763), LSLFF (SEQ ID NO: 764), LSLFG (SEQ ID NO: 765), LSLFH (SEQ ID NO:766), LSLFI (SEQ ID NO: 767), LSLFL (SEQ ID NO: 768), LSLFM (SEQ ID NO:769), LSLFS (SEQ ID NO: 770), LSLFV (SEQ ID NO: 771), LSLFW (SEQ ID NO:772), LYLFT (SEQ ID NO: 773), LVLFT (SEQ ID NO: 774), LSFFT (SEQ ID NO:775), LSGFT (SEQ ID NO: 776), LSKFT (SEQ ID NO: 777), LSCFT (SEQ ID NO:778), LCLFT (SEQ ID NO: 779), LRLFT (SEQ ID NO: 780), LPLFT (SEQ ID NO:781), LWLFT (SEQ ID NO: 782), LKLFT (SEQ ID NO: 783), LDLFT (SEQ ID NO:784), LSYFT (SEQ ID NO: 785), LALFT (SEQ ID NO: 786), WSLFT (SEQ ID NO:787), LSLFA (SEQ ID NO: 788), LSLFQ (SEQ ID NO: 789), LSPFT (SEQ ID NO:790), HSLFT (SEQ ID NO: 791), LSLYT (SEQ ID NO: 792), LILFT (SEQ ID NO:793), KSLFT (SEQ ID NO: 794), CSLFT (SEQ ID NO: 795), LSLFY (SEQ ID NO:796), LSLFK (SEQ ID NO: 797), LSLFC (SEQ ID NO: 798), LFLFT (SEQ ID NO:799), LELFT (SEQ ID NO: 800), LSLKT (SEQ ID NO: 801), LLLFT (SEQ ID NO:802), LSLFD (SEQ ID NO: 803), LSLDT (SEQ ID NO: 804), LSLFE (SEQ ID NO:805), DSLFT (SEQ ID NO: 806), LSLET (SEQ ID NO: 807), LSDFT (SEQ ID NO:808), LSEFT (SEQ ID NO: 809), ESLFT (SEQ ID NO: 810), SLFT (SEQ ID NO:811), LSFT (SEQ ID NO: 812), LFT, LSL, LT, or T, or absent. In someembodiments, X₈₀₃ is an optional sequence, and can be R, F, K, N, R, T,or Y, or absent. In some embodiments, the isolated peptide comprisingFormula (VIII) has a length that is less than or equal to 1100 aminoacids, for example, less than or equal to 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129,130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 150, 160, 170,180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320,340, 360, 380, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900,950, 1000, 1050, or 1100 amino acids, including ranges between any twoof the listed values.

In some embodiments, the immune cells are contacted with an inhibitorthat comprises a peptide comprising, consisting of or consistingessentially of Formula (IX). Accordingly, in some embodiments, thepeptide inhibitor comprises a peptide of Formula (IX):X₉₀₁X₉₀₂X₉₀₃X₉₀₄X₉₀₅X₉₀₆X₉₀₇X₉₀₈X₉₀₉X₉₁₀X₉₁₁X₉₁₂X₉₁₃X₉₁₄X₉₁₅X₉₁₆X₉₁₇,wherein X₉₀₁ is any amino acid or absent; X₉₀₂ is a positively chargedamino acid, F, or N; X₉₀₃ is any amino acid; X₉₀₄ is any amino acid;X₉₀₅ is a polar uncharged amino acid, R, Y, or W; X₉₀₆ is a hydrophobicor uncharged polar amino acid; X₉₀₇ is a hydrophobic or uncharged polaramino acid; X₉₀₈ is a hydrophobic, non-aromatic carbon chain amino acidthat is not M or F; X₉₀₉ is a positively charged amino acid, T, Q, or Y;X₉₁₀ is any amino acid that is not negatively charged; X₉₁₁ is a polaruncharged amino acid or H; X₉₁₂ is any amino acid that is not negativelycharged; X₉₁₃ is any amino acid that is not negatively charged; X₉₁₄ isany amino acid that is not negatively charged; X₉₁₅ is a negativelycharged amino acid, Y, or Q; X₉₁₆ is any amino acid that is notnegatively charged; and X₉₁₇ is one or more positively charged aminoacids or is absent. Optionally, X₉₀₁ comprises a positively chargedamino acid. Optionally X₉₀₁ is an R or K. Optionally X₉₁₇ is RR. In someembodiments, the isolated peptide comprising Formula (IX) has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values.

In some embodiments, the immune cells are contacted with an inhibitorthat comprises, consists of, or consists essentially of a peptideinhibitor that comprises, consists of, or consists essentially of anyone or more of the peptides set forth in Table 5.1. In some embodiments,the isolated peptide from Table 5.1 used in these methods has a lengththat is less than or equal to 1100 amino acids, for example, less thanor equal to 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73,74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107,108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121,122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135,136, 137, 138, 139, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230,240, 250, 260, 270, 280, 290, 300, 320, 340, 360, 380, 400, 450, 500,550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, or 1100 aminoacids, including ranges between any two of the listed values. In someembodiments, the response of the immune cells is detected. In someembodiments, the response to IL-2 stimulation is detected (see Example2). In some embodiments, T cell stimulation is detected (see Example 3).In some embodiments, NK-Cell cytotoxicity is assayed (see Example 4). Insome embodiments, leukocyte spreading is detected (see Example 5). Insome embodiments, unblocking of the LFA-1 receptor is detected (seeExample 6). In some embodiments, binding of P28R to the tumor can bedemonstrated. In some embodiments, binding of P3028 (SEQ ID NO: 185) tothe IL-2 receptor is detected (see Example 8). In some embodiments, MTSconversion by the immune cells is detected, for example in response toimmune cell stimulation (see Examples 31-32). In some embodiments, BrdUincorporation by the immune cells is detected, for example in responseto immune cell stimulation (see Examples 31-32). It is contemplatedherein that some patients will exhibit some immune cell responses inresponse to the inhibitor, but will not exhibit other immune cellsresponses in response to that same inhibitor (see Example 31-32, andFIGS. 34, 37, and 38, showing, among other results, that P28R enhancedthe IL-2 induced stimulation of BrdU uptake and MTS conversion in onepatient, but enhanced BrdU updated and not MTS conversion in anotherpatient). Thus, some embodiments include detecting two or more immunecell responses described herein. Detection of two or more immune cellresponses can allow the identification of a patient that is likely toelicit a first response, but not a second response, and can be useful inguiding clinical decisions such as which inhibitors or combinations ofinhibitors to apply, and whether to apply additional therapies to thepatient in need. In some embodiments, detecting activation orstimulation of an immune cell, as evidenced by an increase in CD69 orCD71 expression, induction of the secretion of a signal substance, asevidenced by interferon gamma or IL-12 production, or stimulation of therelease of a cytolytic substance, as evidenced by the release ofgranzyme B or perforin is performed. In some embodiments, detectingactivation or stimulation of an immune cell includes detecting one ormore of enhanced cytotoxicity, cytokine production, cell migration,and/or cell proliferation

In some embodiments, optionally, an effective dose of the inhibitor forthe patient in need is determined. In some embodiments, cells of thepatient are contacted in vitro with two or more doses of the inhibitor,and an immune response. As shown in FIGS. 33A, 33B, and 34, P28R canhave dose-dependent immunomodulatory effects, for example onmitochondrial metabolism (see Example 28 and 29).

As shown in FIG. 34, increasing doses of P28R (SEQ ID NO: 2) wereprovided to the immune cells of cancer patients in vitro. A dose of 20μg/ml of P28R resulted in significantly higher MTS conversion than adose of 40 μg/ml of P28R. Thus, one skilled in the art will appreciatethat some embodiments include determining an effective dose of aninhibitor for the cells of a patient in vitro, and then providing anappropriate dose of the inhibitor to the patient.

Materials and Methods

Except when stated otherwise, the following materials and or methodswere used as appropriate in the Examples provided below.

Human Serum

Human serum was collected in serum collection tubes without additives(Vacutainer, Becton Dickinson, Franklin Lakes, N.J.) at the same time asblood samples for isolation of PBMC. The sera were heat-inactivated at56EC for 30 minutes.

Isolation of PBMC's

To isolate PBMC's, venous blood was drawn from healthy volunteers orfrom cancer patients in glass vacuum tubes with acid dextrose citratesolution A as anti-coagulant (Vacutainer, Becton Dickinson, FranklinLakes, N.J.). Erythrocytes were removed by sedimentation on 2% dextranT500 solution (Amersham Pharmacia Biotech AB, Uppsala, Sweden) in 0.9%NaCl (this step was omitted for cultures with PHA-stimulation—seebelow). PBMC were then isolated by Ficoll-Paque Plus (GE HealthcareBio-Sciences AB, Uppsala, Sweden) density gradient centrifugation afterwhich the cells were washed twice in RPMI 1640 Dutch's modification(Gibco, InVitrogen AB, Stockholm, Sweden) with 2% human serum albumin(HSA) (Pharmacia & Upjohn, Stockholm, Sweden) (RPMI/2% HSA). For cellcultures with PHA-stimulation, PBMC were washed in Hank's Balanced SaltSolution (HBSS) with 10% autologous plasma instead of RPMI/2% HSA. Cellviability was assessed by exclusion of 0.05% Trypan Blue and was alwaysabove 95%. The cell suspension was stained with TUrk's solution and thenumber of lymphocytes and monocytes in the PBMC preparation were countedin a hemocytometer. PBMCs were suspended in RPMI/2% HSA and the cellconcentration adjusted to 5×105 lymphocytes/ml.

IL-2 Induced Proliferation of PBMC in Uncoated and Coated Culture Plates

Pre-coating of culture plates with HSA and HSA/IgG. Round-bottomed,96-well tissue culture plates (Costar, Corning Inc. NY, US) werepre-coated with HSA only or HSA and pooled human IgG for intravenousinjection (Gammagard, Baxter AS, DK). HSA was diluted in RPMI1640without supplements to a concentration of 10 mg/ml. In some experiments,1 mg/ml IgG was mixed into a solution of 9 mg/ml HSA in RPMI (HSA/IgG).200 μl of HSA or HSA/IgG were then added to each well of the plate. Theplates were incubated at 4° C. for 30 minutes after which the wells werewashed twice with 200 μl of RPMI1640. The coated plates were usedimmediately.

100 μl of RPMI1640 supplemented with 200 IU/ml penicillin, 200 μl/mlstreptomycin, 4 mM L-glutamine (all from Sigma Chemical Co. MO, US) and20% heat-inactivated human serum (autologous or from cancer patients)were added to uncoated, HSA or HSA/IgG coated tissue culture microtiterplates. PBMC, isolated from healthy individuals or patients withmetastatic renal cell carcinoma, were diluted in RPMI/2% HSA at aconcentration of 5×10⁵/ml and 100 μl were added to the microtiter wells.Interleukin-2 (IL-2, Proleukin, Chiron, NL), at a final concentration of120 IU/well, was added to some wells. Cells were cultured for 7 days ina humidified, 5% CO2-atmosphere at 37° C. Proliferation was assayed byincorporation of 1.6 μCi/well of [³H]-thymidine (Amersham Int., UK)during the last 18 hrs. Mean values of dpm (disintegrations per minute)of triplicates were used for the calculations.

Interleukin-2 (IL-2) Induced Proliferation of PBMC in the Presence ofAlbumin Peptides

Cultures for IL-2 induced proliferation was set up with PBMC fromhealthy donors and autologous serum as described above with theexception that PBMC were first pre-incubated for 30 min at roomtemperature with the indicated albumin peptides at a concentration of 10μg/ml.

Interleukin-2 (IL-2) Induced Proliferation of PBMC in the Presence ofAlbumin Peptides in Coated and Uncoated Tissue Culture Plates

Round-bottomed, 96-well tissue culture plates (Costar, Corning Inc. NY,US) were pre-coated with HSA only or HSA and pooled human IgG forintravenous injection (Gammagard, Baxter AS, DK) as follows; HSA wasdiluted in RPMI1640 without supplements to a concentration of 10 mg/ml.A mixture of 1 mg/ml IgG in a solution of 9 mg/ml HSA in RPMI (HSA/IgG)was also prepared. 200 μl of HSA or HSA/IgG were then added to each wellof the plate. The plates were incubated at 4° C. for 30 minutes afterwhich the wells were washed twice with 200 μl of RPMI1640. The coatedplates were used immediately. 100 μl of RPMI1640 supplemented with 200IU/ml penicillin, 200 μl/ml streptomycin, 4 mM L-glutamine (all fromSigma Chemical Co. MO, US) and 20% heat-inactivated human serum(autologous) were added to the HSA or HSA/IgG coated tissue culturemicrotiter wells. PBMC, isolated from healthy individuals, were dilutedin RPMI/2% HSA and peptides were added directly to the cell suspensionat a concentration of 10 μg/ml. One hundred l of this cell suspension(5×10⁴ lymphocytes) was then added per well providing a finalconcentration of 5 μg/ml peptide per well. IL-2 (Proleukin, Chiron, NL),at a final concentration of 120 IU/well, was added to the wells. Cellswere cultured for 7 days in a humidified, 5% CO2-atmosphere at 37° C.Proliferation was assayed by incorporation of 1.6 μCi/well of[³H]-thymidine (Amersham Int., UK) during the last 18 hrs. Mean valuesof dpm (disintegrations per minute) of triplicates were used for thecalculations.

Albumin Peptides

Synthetic albumin peptides were custom prepared by CSBio Co, Menlo Park,Calif. Peptides were >95% pure as confirmed by HPLC. Peptides were keptfreeze dried at minus 20° C. Peptides were reconstituted in sterile H2O(Sigma) for use in ELISA or in RPMI1640 (GIBCO) for use in cell cultureexperiments. Peptides were sterile filtered through a 0.22 μm syringefilter (Millipore Co) before use in cell culture experiments.

ELISA for the Detection of Murine Antibodies Binding to Human Albumin

Duplicate wells in Hibinding microtitre plates (Costar 2592, CorningInc, NY, USA) were coated with 100 μl of dHSA diluted in PBS at variousconcentrations or, alternatively, control albumin sample at the sameconcentrations. The plates were incubated at room temperature overnight.The wells where then washed with wash buffer consisting of 0.05%TWEEN-20 reagent in PBS (Sigma) followed by blocking for 1 h at 25° C.with 200 μl 0.1% gelatin prepared from bovine skin (Sigma) in PBSfollowed by washing in wash buffer. Either of two murine monoclonalantibodies (IgG1) with specificity for denatured, humanalbumin(anti-dAbclh040801 or anti-dAlbclh040809) was added at 1 μg/ml in ELISAreagent diluent (0.01% gelatin (Sigma) and 0.05% TWEEN-20 reagent(Sigma) in 20 mM Tris-buffered saline (TBS, Sigma)). The antibodies wereincubated for 1.5 h at 25° C. followed by washing. Envision-HRP(DakoCytomation Norden A/S, Glostrup, Denmark) was added diluted 1/5 to1/10 in ELISA reagent diluent and incubated for 30 min at 25° C.followed by washing. Finally, a substrate solution consisting of H₂O₂and tetramethylbenzidine (R&D Systems Europe, Ltd, Abingdon, UK) wasadded. The reaction was stopped with 1 M H2SO4 and the optical densitymeasured as absorbance (Abs) at dual wavelengths, 450 nm and 570 nm,with a Multiscan EX microplate reader (Labsystems).

ELISA with Rabbit-anti 3028 Antiserum

Duplicate wells in Hi-binding microtitre plates (Costar 2592, CorningInc, NY, USA) were coated with 100 μl of P3028 (10 ug/ml), denatured HSA(denHSA, 4.5 ug/ml) or control HSA sample (4.5 ug/ml). All coatingreagent were diluted in PBS and incubated at room temperature overnight.The wells where then washed with wash buffer consisting of 0.05%TWEEN-20 reagent in PBS (Sigma) followed by blocking for 1 hr at 25° C.with 200 μl 0.5% gelatin prepared from bovine skin (Sigma) in PBSfollowed by washing in wash buffer. Rabbit preimmune sera or anti-3028sera, diluted 1/1000 000 in ELISA reagent diluent (0.01% gelatin and0.05% TWEEN-20 reagent in PBS), were added and incubated for 1 h at 25°C. followed by washing. Biotinylated horse anti-rabbit/mouse IgG(VECTASTAIN ELITE reagent, Vetor Laboratories Inc, CA, USA) diluted 1/5in ELISA reagent diluent was then added and the plates incubated for 1 hat 25° C. followed by washing. Next, HRP-conjugated strreptavidine(R&Dsystems Europe, Ltd, UK) was added. Finally, after washing in washbuffer, substrate solution consisting of H₂O₂ and tetramethylbenzidine(R&D Systems) was added. The reaction was stopped with 1 M H₂SO₄ and theoptical density measured as absorbance (A) at dual wavelengths, 450 nmand 570 nm, with a Multiscan EX microplate reader (Labsystems).

Statistical Considerations

Comparisons of the means of different patient groups or different testoccasions were performed using an unpaired t-test. Time to progressionand survival was analyzed using the Kaplan-Meier method and Logranktest.

Comparisons between the proliferative response to PHA in differentgroups or at different test occasions were done on logarithmated meanvalues of dpm of triplicates using unpaired t-test. For thedetermination of the effect of addition of CHL on the proliferativeresponse of PHA-stimulated PBMCs, a modulation index (MI) was calculatedaccording to the following formula: MI=log (dpm PHA+drug/dpm PHA).

EXAMPLE 1 Serum Peptides with Immune Inhibitory Activities

Identification of Immunoregulatory Peptides

An artificial cell surface (ACS) was prepared by selectivelybiotinylating cell surface structures of PBMCs and after lysing thecells binding the biotinylated proteins to streptavidin columns (seeExample 17 for further description of the ACS). The mixture of peptidesobtained after trypsination was adsorbed by ACS and the binding peptideswere identified by comparing adsorbed and unabsorbed peptide solutionsusing the MALDI TOF ms technique. Based on their degree of binding andtheir spatial relation to previously identified immunoregulatorystructures, four new peptides were selected to be synthesized andinvestigated for their immunoregulatory activity, primarily the effecton the proliferative response to IL-2. One of these peptides, P3028 (SEQID NO: 185) was found to have multiple immunoinhibitory activities.

Expression of the P3028 Epitope in Malignant Tumors

Rabbit polyclonal antibodies against P3028 were generated and affinitypurified (see Example 9). To determine the localization of P3028 intumor cells, sections of malignant metastases were immunostained usingthe anti-P3028 rabbit polyclonal antibodies. Tissue sections wereprepared from formalin fixed biopsies from cancer patients. Sectionswere de-paraffinased and blocked with 10% normal, human AB-serum inHank's balanced salt solution supplemented with 0.01 M Hepes (BSS, GIBCOBRL) for one hour prior to staining. Sections were then stained with 10ug/ml affinity purified rabbit anti-P3028 diluted in BSS with 2%AB-serum and 0.1 μg/ml saponin for 30 min. After washing in BSS with 0.1μg/ml saponin, Ultravison One alkaline phosphatase polymer specific formouse and rabbit Ig (Lab Vision Co., CA, USA) was added. Excess polymerwas then washed from the sections with BSS with 0.1 g/ml saponin. Boundpolymer complex was the detected by naphthol phosphate substrate andliquid Fast Red chromogen (Lab Vision Corp.) The sections were counterstained in Mayer's haematoxylin and mounted in Glycergel. As shown inFIG. 1, structures 1 to which anti-P3028 antibodies bind are widelyexpressed in human malignant tumors, e.g., malignant melanoma, renalcell carcinoma and colorectal cancer.

Western blotting was performed on extracts of malignant melanomametastases to detect the presence of P3028 structures. Western blottingwas performed using standard techniques, and P3028 structures weredetected using affinity purified Rabbit polyclonal antibodies againstP3028 (see Example 9). P3028 structures in tumor extracts from malignantmelanoma metastases were identified in the extracts of 7 out of 7mestases from 4 patients that were screened (see FIG. 2). The P3028peptide was present in all patients. Additionally, the P3028 structurewas present in full-length albumin. In addition this structure was foundin larger molecules. These results are compatible with the P3028structure being generated not only by proteolytic fragmentation but alsoby denaturation.

Occurrence of P3028 Structures in Serum

Substances exposing the structure of P3028 were determined in humanserum by using affinity purified antibodies in a sandwich ELISA. Thatis, the ability to detect P3028 structures in human serum was confirmed.

A sandwich ELISA was performed to detect albumin exposing the P3028epitope in serum as follows: An affinity polyclonal purified rabbitantisera, specific for human albumin P3028, was coated onto high proteinbinding ELISA microwells (capture antibody; see Example 9). A 1%solution of heat-inactivated serum (from a serum pool of 5 healthycontrol samples, 1 healthy control serum sample and 2 sera obtained fromcancer patients), spiked with increasing concentrations of P3028, wasthen added to the wells. After washing, a biotinylated mouse anti-humanalbumin monoclonal antibody was added and the amount of bound antibodywas detected with HRP-conjugated streptaviddin and TMB chromogensubstrate. (One representative experiment out of two is shown FIG. 3).

The amount of P3028 structures were determined as the amount of P3028,which inhibits 50% of the binding of P3028 structures in the serum tothe capture antibody (see FIG. 3). The serum concentration wasdetermined to be in the range of 1.2-1.6 μg/ml P3028 equivalents in oneserum pool from 5 healthy control samples, 1 healthy control serumsample and 2 sera obtained from cancer patients. The amount of theseP3028-substances in serum can be considerably more as the molecularweight of albumin is about 35 times more than that of P3028. The epitopespecific reactivity of P3028-substances was accurately determined usingthe methods of this Example.

EXAMPLE 2 Effect of ACS-identified Peptides on IL-2 InducedProliferation

Human Ex Vivo Model for Immunosuppression in Cancer Patients

Interleukin-2 (IL-2) plays a major role in initiation and activation ofan immune response and its capacity to induce lymphokine activatedkiller cells (LAK-cells), T-cell proliferation and cytotoxicity.Accordingly, a human ex vivo model of IL-2 stimulation of immune cellswas developed. This model was useful for studying the effects of immunesystem modulators, such as P3028, and inhibitors thereof.

The model included PBMCs isolated from venous blood samples from healthyblood donors (control samples) or cancer patients. One hundred pI ofculture medium (RPMI 1640 Dutch's modification (Gibco, InVitrogenAB,Stockholm, Sweden) supplemented with 200 IV/ml penicillin, 200 ug/mlstreptomycin, 4 mM L-glutamine (all from Sigma Chemical Co. MO, US) and20% heat-inactivated human serum) were added to roundbottomed, 96-welltissue culture plates (Costar, Corning Inc. NY, US). One hundred ul ofPBMCs in RPMI/2% HSA (5×104 lymphocytes) was then added per wellfollowed by IL-2 (Proleukin, Chiron, NL) at a final concentration of 120IU/well. Control sample wells without IL-2 was set up in parallel. Cellswere cultured for 7 days in a humidified, 5% CO2-atmosphere at 37° C.Cell proliferation was assayed by incorporation of 1.6 pCi/well of[³H]-thymidine (Amersham Int., UK) during the last 18-24 h hrs. Meanvalues of dpm (disintegrations per minute) of triplicate wells were usedfor the calculations.

IL-2 induced proliferation by PBMC from healthy control samples and PBMCfrom renal cell carcinoma patients (RCC) cultured in 10% autologous serawas studied using this model. Results of the study are shown in FIG. 4.IL-2 induced proliferation was significantly reduced (p<0.0002) forPBMC's cultured in serum of a renal carcinoma patient as compared to ahealthy control sample.

Correlation Between IL-2 Response in Ex Vivo Model and Overall Survivalof Renal Cell Carcinoma Patients

The response to IL-2 in this model was demonstrated to correlate tooverall survival of renal cell carcinoma patients. Patients, included inthe analyses of over-all survival according to proliferative response ofPBMCs to interleukin-2, were diagnosed with systemic metastatic renalcell carcinoma. They were previously untreated and scheduled forInterleukin-2 treatment (Proleukin, Chiron, NL). Blood samples weretaken prior to initiation of treatment. Survival curves were plottedusing the method of Kaplan and Meier and time to progression andsurvival comparisons between subgroups were performed using the log ranktest. In addition, the prognostic significance of the level ofLPS-stimulated IL-6 production was also calculated using Cox regression.

FIG. 5 illustrates a Kaplan Meyer analysis of renal cell carcinomapatients according to proliferative response to IL-2. Patients wereclassified as having a proliferative response of >30,000 dpm 52,15,000-30,000 dpm 54, or <15,000 dpm 56. A log rank analysis weperformed, and overall patient survival correlated with proliferativeresponse (p=0.0042). As illustrated in FIG. 5, patients with the lowestIL-2 induced proliferation of PBMCs in autologous serum in the ex vivomodel 56 also had the lowest overall survival time. Thus, a lowproliferative rate indicates a poor survival.

Effect of Different Peptides on IL-2 Induced Proliferation

The effect of different peptides on IL-2 induced proliferation wasanalyzed in the human ex vivo model, using PBMCs from healthy controlsamples. PBMCs were cultured for 7 days in the presence of IL-2 (20U/ml) and the peptides. A control sample was also performed in which nopeptide was added (“None”). Proliferation was measured as incorporationof ³H-thymidine during the final 18 hours. The peptides included P3026(SEQ ID NO: 183), P3027 (SEQ ID NO: 184), P3028 (SEQ ID NO: 185), andP3029 (SEQ ID NO: 186). One of the peptides, P3028, regularly inhibitedIL-2 induced proliferation (p<0.0006, as compared to control sample;n=17), but none of the other peptides identified by their binding to theartificial cell surface had any inhibitory activity (For P3026, P3027,P3029 n=4 or 5). FIG. 6 illustrates the analysis of the effect of thefour different peptides.

The inhibition of the proliferative response to IL-2 by P3028 was alsoobserved for cancer patient PBMCs studied in the human ex vivo model.The ex vivo model of IL-2 stimulation was constituted using the PBMCs ofa cancer patient, and IL-2 stimulation was compared in the presence andabsence of P3028. As illustrated in FIG. 7, the inhibitory activity ofP3028 on IL-2 induced proliferation can be demonstrated also in cultureswith cancer patient PBMCs, even if the response to IL-2 was alreadysuppressed (see FIG. 7).

EXAMPLE 3 Effect of P3028 on T-Cell Receptor Stimulation

To examine the effects of P3028 on T cell receptor stimulation, Bloodfor PBMC isolation was provided from healthy control samples in 50 mltransfusion bags with acid dextrose citrate solution A . . . Whole bloodwas diluted 1:1 in PBS containing 2 mM EDTA. PBMCs were then isolated byFicoll-paque Plus (GE Healthcare Bio-Sciences AB, Sweden) densitygradient centrifugation after which the cells were washed first in PBSwith 2 mM EDTA and second in lymphocyte culture media. Cell viabilitywas assessed by exclusion of 0.02% Trypan Blue and was always above 95%.The cell suspension was counted in a haemocytometer. PBMCs weresuspended in the culture medium without sera and the cell concentrationadjusted to 1×10⁶ lymphocytes/ml for proliferation assays and 6.4×10⁵for migration assays respectively. The lymphocyte culture medium RPMI1640 (Invitrogen, Sweden) was complemented with 1%Penicillin/Streptomycin (Invitrogen, Sweden) and 4 mM Gluta-Max(Invitrogen, Sweden). For CD3 induced proliferation the plates werecoated with purified anti-human CD3 antibodies (BD Pharmingen, Sweden).Therefore 50 μl of 2.5 μg/ml antibody PBS solution were pipetted intoeach well incubated for 1 hour. Cells were cultured for 4, 5 or 7 daysin a humidified, 5% CO2-atmosphere at 37° C. Cell proliferation wasassayed by the mitochondrial activity test CellTiter 96® AQueousNon-Radioactive Cell Proliferation Assay (MTS, Promega, Sweden) duringthe last 4 hours. To each well 10 μl of the MTS solution was added andmeasured after 4 hours of incubation at 37° C. The measured values ofthe reference dye were subtracted of each well. The peptide solutionswere prepared by dissolving peptides 3028, SCF28R, 28209 and SCF27(Schafer-N, Copenhagen, Denmark) in lymphocyte media to a concentrationof 25 μg/ml. The final concentration in the cultures was 5 or 10 μg/ml.

T cells were stimulated in cultures on plates pre-coated with amonoclonal antibody directed against CD3 and the number of metabolicallyactive cells (i.e., cell proliferation) was determined using MTSstaining after 3 to 7 days of culture. Detection of solid phase CD3monoclonal antibody was used as a measurement of T cell proliferation.FIG. 8 illustrates the effect of P3028 on TCR stimulated lymphocyteproliferation of PBMCs from four healthy persons. For each person,proliferation of lymphocytes was measured in the absence of stimulation82, IL-2 stimulation 84, treatment with P3028 alone 86, and IL-2stimulation plus P3028 88. Bars of the bar graph of FIG. 8 are in thesame order for each person.

As can be seen in FIG. 8, P3028 had an inhibitory effect in at leastthree out of four experiments (p<0.001). It is unlikely that reduced MTSstaining caused by P3028 was be due to a reduced cell metabolism. Takentogether, the results from both models of lymphocyte proliferation, areduced metabolism should reasonably reduce the endogenous thymidinepools and thereby result in an increased uptake of exogenousthymidine/specific activity of the thymidine pools, which then should beerroneously registered as an enhanced proliferation. The ³H-TdR wasactually reduced in these experiments, indicating inhibition ofproliferation.

EXAMPLE 4 Effect of P3028 on NK-Cell Cytotoxicity

The NK-cell cytotoxic activity of blood mononuclear cells from fourhealthy donors was tested. Mononuclear cells were separated by standardFicoll-paque Plus (Pharmacia AB, Sweden) density gradient centrifugationfrom heparinized blood obtained from healthy donors. NK cell cytotoxicactivity of the mononuclear cells was then tested using a commercial kit(NKTEST, Orpegen Pharma GmblI, Heidelberg, Germany) following themanufacturers protocol. Briefly, the kit contains cryopreserved,NK-sensitive target cells (K562) labeled with a lipophilic greenfluorescent membrane dye, which enables discrimination of effector andtarget cells. After incubation with effector cells, killed target cellsare identified by a DNA-stain, which penetrates and specifically stainthe nuclei of dead target cells. This way the percentage of killedtargets can be determined by flow cytometry. The mononuclear cells werepreincubated for 30 min at 37° C. with the indicated peptides (peptideshave been described previously) at 10 ug/ml. Target cells were thenadded, giving an effector:target ratio of 40:1, and the cell mixtureincubated at 37° C. for 3-4 hours. Samples were analysed on aFACSCalibur (BD Biosciences, San Jose, Calif.).

FIGS. 9A-B illustrate the effect of albumin peptides on NK-cellcytotoxicity (p=0.015, paired t-test, normal transformation log-values).As shown in FIG. 9A-B, the presence of P3028 and, to a lesser degree,peptide 3026 reduced the percent specific lysis of K562 target cells byall four donors. Inhibition was not seen in the presence of the controlsample peptide 3027 with no structural relationship with P3028.Inhibition of NK-cell cytotoxicity, in this model, was not due to aneffect of P3028 on the activity of IL-2 as no IL-2 was added to theshort-term cultures.

EXAMPLE 5 Effect of P3028 on Leukocyte Spreading and Immune CellMigration

In properly functioning immune systems, immune cells are recruited totissues, and migrate within tissues. The effect of P3028 in twofunctional tests, leukocyte spreading and immune cell migration wasinvestigated.

Leukocyte Spreading

To analyze the effect of P3028 on leukocyte spreading, buffy coat cellswere prepared from heparinized blood by Dextran assisted sedimentation.These cells were then washed twice in PBS and transferred to slideswashed in 70% and 96% ethanol. The cell suspension was dropped onto theslides and incubated for 15 min in a moist chamber with or withoutP3028, 10 μg/ml, the solution was carefully drained off, the slides wereair dried and stained in May Grünewals Giemsa for 1 minute. As shown inFIG. 10A, the cells strongly adhered to the glass surface and spreadout. Pre-treatment of these cells with P3028 efficiently inhibited thespreading (see FIG. 10B).

Immune Cell Migration

Blood for PBMC isolation was provided from healthy control samples in 50ml transfusion bags with acid dextrose citrate solution A. Whole bloodwas diluted 1:1 in PBS containing 2 mM EDTA. PBMCs were then isolated byFicoll-paque Plus (GE Healthcare Bio-Sciences AB, Sweden) densitygradient centrifugation after which the cells were washed first in PBSwith 2 mM EDTA and second in lymphocyte culture media. Cell viabilitywas assessed by exclusion of 0.02% Trypan Blue and was always above 95%.The cell suspension was counted in a haemocytometer. PBMCs weresuspended in the culture medium without sera and the cell concentrationadjusted to 1×10⁶ lymphocytes/ml for proliferation assays and 6.4×10⁵for migration assays respectively. The lymphocyte culture medium RPMI1640 (Invitrogen, Sweden) was complemented with 1%Penicillin/Streptomycin (Invitrogen, Sweden) and 4 mM Gluta-Max(Invitrogen, Sweden). For CD3 induced proliferation the plates werecoated with purified anti-human CD3 antibodies (BD Pharmingen, Sweden).Therefore 50 μl of 2.5 μg/ml antibody PBS solution were pipetted intoeach well incubated for 1 hour. Cells were cultured for 4, 5 or 7 daysin a humidified, 5% CO₂-atmosphere at 37° C. Cell proliferation wasassayed by the mitochondrial activity test CellTiter 96® AQueousNon-Radioactive Cell Proliferation Assay (Promega, Sweden) during thelast 4 hours. To each well 10 μl of the MTS solution was added andmeasured after 4 hours of incubation at 37° C. The measured values ofthe reference dye were subtracted of each well. The peptide solutionswere prepared by dissolving peptides 3028, SCF28R, 28209 and SCF27(Schafer-N, Copenhagen, Denmark) in lymphocyte media to a concentrationof 25 μg/ml. The final concentration in the cultures was 5 or 10 μg/ml.

50 μl of the prepared 6.4×10⁵ PBMC dilution were pipetted intoEppendorfs tubes and centrifuged for 5 minutes at 400 g, then theprepared dilutions of blank, P3028 and the inhibitors were added. ThePBMCs were incubated at the 37° C. with the test substances for onehour. Meanwhile the Boyden Chamber was prepared by pipetting 25 μl ofeither media without fMLP or media containing 1×10-8M fMLP to the lowerwells. Then 50 μl of the PBMCs final concentration, 3,2×104, weretransferred to the upper wells of the chamber. The PBMCs were allowed tomigrate for one hour at the 37° C. The filters were removed and storedin 70% ethanol overnight. Thereafter the filters were dehydrated inincreasing alcohol concentration and finally placed in Xylene.Subsequently they were placed on slides, mounted and counted with amicroscope, containing a am scale. Each test was done in duplicates andmigration was calculated as percentage of the mean of the blankduplicates without fMLP. As shown in FIG. 11, P3028 is a potentinhibitor of immune cell migration across the membrane of the Boydenchamber (p<0.002). Migration for healthy control samples (N=6) isillustrated in FIG. 11 using dark bars (left), while cancer patients(N=3) are shown as light bars (right). In FIG. 11, Error bars: 95% CI.P3028 reduced the migration of PBMCs of both healthy cells and cancerpatients.

EXAMPLE 6 Further Characterization of the Effect of P3028 on IL-2Induced Proliferation

The C and N-terminal parts of P3028 were synthesized and analyzedseparately and in combination. The inhibitory activity of these twoparts of P3028 alone or in combination is much weaker (see FIG. 12) andthey do not inhibit the effect of P3028 on IL-2 induced proliferation(see FIG. 13) in the ex vivo human model. FIG. 12 illustrates effects ofthe C-(P3218) (SEQ ID NO: 187) and N-terminal (P3325) (SEQ ID NO: 186)parts of P3028 on 11-2 induced proliferation in comparison with theeffect of the full length P3028. One representative experiment is shown.FIG. 13 illustrates that the inhibitory effect of P3028 on IL-2 inducedproliferation is not neutralized by the C-(P3218) and N-terminal (P3325)parts of P3028 alone or in combination.

EXAMPLE 7 Binding of P3028 to LFA-1

The presence of β2-integrins on PBMCs was demonstrated byimmunocytochemical staining. The occurrence of factors interfering withthe binding of monoclonal antibodies directed against β2-integrins incancer patient sera was analysed by staining of β2-integrins on PBMCs. Astandard immunohistochemical staining procedure using acetone fixation,10% human AB-serum for blocking, incubation with anti-LFA-1 antibody.PBMCs were separated as described above and immediately spun down onpre-cleaned microscope slides in a Shandon Cytospin (Shandon ScientificLtd, UK) at 1000 RPM for 7 min at 5×104 cells per slide. The slides wereleft to dry at room temperature over night, after which they werewrapped in parafilm and stored at 70° C. Immediately before use, thecytospins were thawed and fixed with acetone for 5 min at roomtemperature. The cytospins were first blocked with 10% normal humanAB-serum with and without albumin peptides (40 μg/ml) or serum fromcancer patients for 1 h before staining. Primary antibody, consisting ofa monoclonal mouse anti-human CD11a (BD Biosciences) diluted in Trisbuffered saline (TBS, pH 7.6) at 1 μg/ml (PBMC), was added. The slideswere incubated for 30 min and then washed in TBS followed byEnvision-Alkaline Phosphatase (Dako Norden A/S, Denmark) or,alternatively, Ultravision-Alkaline Phosphatase (Lab Vision Co) for 30min. After additional washing in TBS, the slides were incubated inalkaline phosphatase substrate consisting of Fast Red TR salt (Sigma),naphtol AS-MX (Sigma) and 5 mM levamisol (Sigma) to block endogenousalkaline phosphatase activity, for 20 min followed by washing in TBS.They were then counterstained in Mayer's haematoxylin for 1 minute andmounted in Glycergel (Dako Norden A/S). Monoclonal mouse IgG1 against anirrelevant antigen (Aspergillus niger glukosoxidase, Dako Norden A/S)was used as a negative control sample. All incubations were performed atroom temperature in a moist chamber.

Pre-incubation with peptides added to the AB serum was either no peptideadded (see FIG. 15A), or P3028 added (see FIG. 15B). Notably, theanti-LFA-1 antibody used in these experiments was a potent inhibitor ofIL-2 induced proliferation.

As shown in FIG. 14, the presence of β2-integrin blocking factors wasthen demonstrated as a reduced stainability 5 of these cells afterincubation with cancer patient sera (see FIG. 14B), compared topreparations pre-incubated with control serum sample (see FIG. 14A)which showed strong staining 3 for LFA-1.

As shown in FIG. 15, similar to the results described for cancer patientsera, treatment with P3028 can modulate the binding of the LFA-1antibody to LFA-1 of mononuclear blood cells, FIG. 15 illustratesinhibition of the binding of an anti-LFA-1, mAb, to mononuclear bloodcells by P3028. Strong staining 3 for LFA-1 was observed in cells inwhich no peptide was added (see FIG. 15A), while weak staining 5 forLFA-1 was observed in cells in which P3028 was added (see FIG. 15B).

In order to further demonstrate the blockade of LFA-1 by the P3028structure, the staining of this integrin on PBMCs from healthy controlsamples and cancer patients was compared. FIG. 16 illustrates stainingof LFA-1 on PBMCs from a healthy control sample (see FIG. 16A), and acancer patient before (see FIG. 16B) and after (see FIG. 16C) treatmentwith an antibody directed against P3028. As shown in FIG. 16A, a clearmembrane staining 3 is found on PBMCs from healthy control samples incontrast to PBMCs from a patient with advanced cancer, which exhibitedweak staining 5. However, when the PBMCs from this patient wereincubated with an antibody directed towards the P3028 structure for 24hours the membrane staining appeared 3, indicating that the antibodybound the P3028-structure and thereby unblocked LFA-1 (see FIG. 16C).

Similarly, as shown in FIG. 17, incubation of PBMCs from a healthycontrol sample with either P3028 or serum from a cancer patient blockedthe membrane staining of LFA-1. FIG. 17 illustrates staining 3 ofmononuclear blood cells by an anti-LFA-1 antibody (A) is blocked 5 byP3028 (B) or cancer patient serum (C).

EXAMPLE 8 Binding of P3028 to the α-Chain (CD25) of the IL-2 Receptor

Because P3028 significantly inhibits the proliferative response to IL-2,the effect of P3028 on the binding of IL-2 to its receptor, CD25 wasstudied. The fusion protein of CD25 and the Fc-part of IgG was bound toprotein G coated micro-plates/ELISA plates and the plates were incubatedwith biotinylated IL-2 with or without P3028 present. FIGS. 18-Billustrate the results of this ELISA analysis for dilution ofbiotinylated IL-2 that were as follows: (diamond ♦) 1:300, (square ▪)1:600, (triangle ▴; see FIG. 18B) no biotinylated IL-2. The binding ofbiotinylated IL-2 to rhuIL-2R alpha was increased by increasing amountsof P3028. Surprisingly, the binding of IL-2 to CD25 was enhanced byP3028, indicating a three-part interaction between IL-2, CD25 and P3028(see FIGS. 18-B). Even if the binding of IL-2 to CD25 is enhanced theproper assembly of the high affinity receptor and/or signal transductionis blocked as P3028 is a potent inhibitor of IL-2 induced proliferation.

It was demonstrated using computer assisted molecular modeling thatP3028 binds to CD25 at the IL-2 binding site (see FIG. 19). The crystalstructure of the IL-2 receptor bound to IL-2 is known in the art (seeWang et al., Science 2005, 310(5751): 1159-1163, and Stauber et al,Proc. Natl. Acad. Sci. USA 2006, 103(8): 2788-2793, each of which ishereby incorporated by reference in its entirety), and binding of P3028was modeled according. In FIG. 19, the α-chain 190 of the IL-2 receptor(CD25) binding P3028 192 (A) at the IL-2 binding site 194 (B) isdepicted. IL-2 196 is also shown.

EXAMPLE 9 Antibodies that Bind to P3028

Rabbit antisera directed against the albumin P3028 were generated. P3028was synthesized with a cysteine added to the N-terminus end and thenconjugated with keyhole limpet hemocyanin (KLH) as a carrier protein.Polyclonal antisera were generated by repeated immunizations of rabbitswith KLH-conjugated P3028 and Freund's adjuvants. For some experiments,the antisera were affinity purified by chromatography onP3028-conjugated Ultralink lodoacetyl gels (Pierce Biotechnology Inc.).For cell culture experiments, buffer exchange to RPMI 1640 Dutch'smodification (Gibco, InVitrogen AB, Stockholm, Sweden) was performed bypassage over PD-10 sephadex columns (Amersham Biosciences, Uppsala,Sweden) followed by filter sterilization on 0.22 m Millex syringefilters (Millipore Co., MA, USA). Rabbit immunizations and purificationof antisera were carried out by Agrisera AB, Sweden.

Two antisera, R and L, from two different rabbits were tested for theirability to bind human serum and denatured Human Serum Albumin (dHSA).Human serum albumin commercially available for therapeutic purposes wastested, heated 10 times in order to be virus free. Wells were coatedwith the P3028, dHSA, or control sample treated (not denatured, butheated 10 times) HSA, which has been prepared just as the denatured HSAexcept for the denaturation procedure. As shown in FIG. 20, antisera,but not preimmune sera, from two rabbits immunized with the albuminP3028 bind to plates coated with the P3028 204, dHSA 206 and, to alesser extent, to control sample treated HSA 208. No substantial bindingwas detected for wells with no coat 202. Thus, rabbit antisera directedagainst the albumin P3028 binds to dHSA and to a lesser extent tocontrol sample HSA.

The binding of the rabbit anti-P3028 serum to P3028 fragments wasassayed using competition ELISA assay. Rabbit antisera, diluted 1/1000000 in ELISA reagent diluent, was pre-incubated for 1 hr at roomtemperature with the indicated concentrations of the peptides. 100 μl ofthe monoclonal antibody alone, or, alternatively, the monoclonalantibody mixed with peptides, was then added to P3028 coated wells andthe ELISA carried out. Inhibition of the binding of rabbit anti-P3028serum L to wells coated with the P3028 was determined for albuminpeptides 2607 (SEQ ID NO: 192), 3218 (C terminal of P3028) (SEQ ID NO:187), 3325 (N terminal of P3028) (SEQ ID NO: 186), and full-length P3028(SEQ ID NO: 185). Peptide 2607, containing the E5K structure, was usedas a negative control sample. As shown in FIG. 21, these serumantibodies bound preferentially to the 3325 but not to the 3218 fragmentof P3028. Similar results are also obtained with the affinity purifiedantibodies.

The effects of affinity purified antibodies directed against P3028 onthe proliferative response to IL-2 were studied in the ex vivo model,using PBMCs from immunosuppressed cancer patients and normal controlsamples. Cultures to test the immunomodulatory effect of affinitypurified rabbit antibodies specific for 3028 were performed as describedabove for IL-2 induced proliferation with the following exceptions; 2%HSA was omitted from the washing medium and from the PBMC suspensionmedium. Serum containing culture medium (100 μl/well) was pre-incubatedwith 20 μg/ml of rabbit antibodies for 30 min at room temperature beforethe addition of 100 μl PBMC suspension to the culture wells.

P21 had renal cell carcinoma and p26, p28 and p29 had malignantmelanoma. As shown in FIG. 22, affinity-purified rabbit antibodiesagainst P3028 overcame inhibition of the proliferative response to IL-2in immunosuppressed cancer patients (FIG. 22A). In normal controlsamples with normal proliferative response to IL-2, no effect ofaddition of these antibodies was seen (see FIG. 22B) (antibody: R.,cancer patients, p=0.0002, paired t-test, normal transformationlog-values). In normal control samples with down-regulation of theimmune reactivity having a proliferative rate of less than 100,000 dpm,the proliferative rate was stimulated similar to the situation incultures from cancer patients.

Polyclonal rabbit IgG was added to control sample cultures in order tomake sure that the effect of the affinity purified antibodies was notdue to an unspecific activity of rabbit IgG in this model. Rabbit IgGhad only minimal activity. The specificity of the anti-P3028 antibodieswas further demonstrated as the stimulatory effect of these antibodieswas neutralized by a small amount of P3028 having no inhibitory activityper se. Similar to the results in the autologous ex vivo model, theimmunosuppressor activity of sera from persons with a low proliferativeresponse to IL-2 was over-come by addition of the anti-P3028 antibodiesto the cultures.

EXAMPLE 10 Peptides that Bind to P3028

The information obtained by studying the effect of cancer patient seraand the synthetic peptide P3028, on staining of the α-chain, CD11a, ofLFA-1 on PBMCs was used in order to design the structure of a potentialbinder/inhibitor of the immunomodulatory peptide P3028. The epitope ofthe particular monoclonal mouse antibody used, HI 111, was mapped toresidues 249-300 of CD11a (Ma Q, et al., J Biol Chem. 2002;277:10638-41). Based on complementarity of charged and hydrophobic aminoacid sequences the first candidate binding to the P3028 peptide wasdesigned. This sequence was then optimized by synthesizing and testingthe binding efficacy of candidate peptides where each amino acid wassubstituted for all 19 L-amino acids.

Three candidate peptide inhibitors of P3028 sequences/structures wereidentified and their blocking capacity in solution was tested. Potentialpeptide inhibitors of P3028 were synthesized on a chip. The linearand/or CLIPS peptides were synthesized based on the amino acid sequenceof the target protein using standard Fmoc-chemistry and deprotectedusing trifluoric acid with scavengers. The constrained peptides weresynthesized on chemical scaffolds in order to reconstruct conformationalepitopes, using Chemically Linked Peptides on Scaffolds (CLIPS)technology (Timmerman et al. (2007)). For example, the single loopedpeptides were synthesized containing a dicysteine, which was cyclized bytreating with alpha, alpha′-dibromoxylene and the size of the loop isvaried by introducing cysteine residues at variable spacing. If othercysteines besides the newly introduced cysteines are present, they werereplaced by alanine. The side-chains of the multiple cysteines in thepeptides are coupled to CLIPS templates by reacting onto credit-cardformat polypropylene PEPSCAN cards (455 peptide formats/card) with a 0.5mM solution of CLIPS template such as 1,3-bis (bromomethyl) benzene inammonium bicarbonate (20 mM, pH 7.9)/acetonitrile (1:1(v/v)). The cardswere gently shaken in the solution for 30 to 60 minutes while completelycovered in solution. Finally, the cards are washed extensively withexcess of H₂O and sonicated in disrupt-buffer containing 1 percentSDS/0.1 percent beta-mercaptoethanol in PBS (pH 7.2) at 70° C. for 30minutes, followed by sonication in H₂O for another 45 minutes. Thebinding of His-tagged P3028 to each peptide was tested in aPEPSCAN-based ELISA. The 455-well credit card format polypropylene cardscontaining the covalently linked peptides are incubated with peptidesolution for example consisting of 1 micrograms/mL diluted in blockingsolution, for example 4% horse serum, 5% ovalbumin (w/v) in PBS/1% TWEENreagent. After washing, the peptides were incubated with a monoclonalmouse anti-his tag antibody (1/1000, Novagen, 70796-3) and subsequentlyafter washing with a rabbit-anti-mouse antibody peroxidase conjugate(1/1000, Southern Biotech, 6175-05) for one hour at 25° C. Afterwashing, the peroxidase substrate 2,2′-azino-di-3-ethylbenzthiazolinesulfonate (ABTS) and 2 microlitres of 3 percent H₂O₂ were added. Afterone hour, the color development was measured. The color development wasquantified with a charge coupled device (CCD)—camera and an imageprocessing system.

The raw data (Raw Data: Optical density, Arbitrary OD units) are opticalvalues obtained by a CCD-camera. The values mostly range from 0 to 3000,a log scale similar to 1 to 3 of a standard 96-well plate ELISA-reader.First the CCD-camera makes a picture of the card before peroxidasecoloring and then again a picture after the peroxidase coloring. Thesetwo pictures are substracted from each other which results in the datawhich is called raw-data. This is copied into the Peplab™ database. Thenthe values are copied to excel and this file is labeled as raw-datafile. One follow-up manipulation is allowed. Sometimes a well containsan air-bubble resulting in a false-positive value, the cards aremanually inspected and any values caused by an air-bubble are scored as0.

As shown in Position 17, 22 and 26 contained good binders of P3028(PGE73=His-tag-P3028). As shown in the diagram, peptide SCF28 and SCF29efficiently block the binding of P3028 (PGE73) but SCF27 does not.Peptide SCF28 (SEQ ID NO: 1), had a solubility good enough to allowtesting in biological human ex vivo models. Based on this structure,peptide P28R (SEQ ID NO: 2) was developed. For each position, shown aredata for no peptide added assay in PBS buffer 230, SCF027 assay in PBSbuffer 232, SCF029 assay in PBS buffer+10% DMSO 234, no peptide added inPBS buffer+10% DMSO 236, and SCF028 assay in PBS buffer+10 DMSO 238. Inthe bar graph of FIG. 23, bars representing each assay were in the sameleft-to-right order for each position. Each peptide, when present in anassay, was at a concentration of 0.5 mg/mL.

EXAMPLE 11 Peptide Interactions with P3028

The information obtained by studying the effect of cancer patient seraand the synthetic peptide P3028, on staining of the alpha-chain, CD11a(SEQ ID NO: 248), of LFA-1 on PBMCs was used in order to design thestructure of a potential binder/inhibitor of the immunoinhibitorypeptide P3028. The epitope of the particular monoclonal mouse antibodyused, HI111, was mapped to residues 274-325 of CD11a, (SEQ ID NO: 248)(UniProt accession code P20701; Ma Q, et al., J Biol Chem. 2002; 277:10638-41). Based on complementarity of charged and hydrophobic aminoacid sequences (see FIG. 31) the first candidate binding to the P3028peptide was designed using the sequence comprising 312-326 of CD11a.This resulted in the peptide KKL15 (SEQ ID NO: 1).

Peptide KKL15 (SEQ ID NO: 1), for example appears to be complementary toP3028. As shown in FIG. 31, positively charged amino acids interact withnegatively charged amino acids of P3028 and hydrophobic amino acids makehydrophobic contacts enhancing the interaction.

EXAMPLE 12 Peptides that Bind to P3028

Based on the structure of peptide P28R, additional peptides wereidentified that bind to P3028. The additional binders includeddeletions, truncations, and or amino acid substitutions of peptide P28R.Binding of peptides to P3028 was assayed using PEPSCAN technology.PEPSCAN technology, or “rampo” assays are biochemical binding assays,details of which are provided below:

A peptide microarray screening technology was used to measure binding ofP28R (SEQ ID NO: 2) and variants of P28R to P3028 (SEQ ID NO: 185). Inthis technology libraries of synthetic peptides are synthesized andcovalently linked onto polypropylene microarray chips. The linearpeptides were synthesized onto credit-card format polypropylene cards(455 peptide formats/card) as described by (Timmerman et al., 2004)using standard Fmoc-chemistry using hexamethylenediamine (HMDA) aslinker and deprotection using trifluoroacetic acid (TFA) withscavengers.

The binding of His-tagged P3028 to each peptide on the card was testedin an ELISA assay. The 455-well credit card format polypropylene cardscontaining the covalently linked peptides were incubated with His-taggedP3028 peptide (PGE73) solution consisting of 0.5 μg/mL diluted inblocking solution (4% horse serum, 5% ovalbumin (w/v) in PBS/1% TWEENreagent). After washing, the peptides were incubated with a monoclonalmouse anti-His-tag antibody (Novagen, 70796-3, diluted 1/1000 in theincubation buffer) and subsequently after washing with arabbit-anti-mouse antibody peroxidase (Rampo) conjugate (SouthernBiotech, 6175-05, diluted 1/1000), for one hour at 25° C. After washing,the peroxidase substrate 2,2′-azine-di-3-ethylbenzthiazoline sulfonate(ABTS) and 2 μL of 3% H2O2 were added. The binding capacity of the mAbwas measured as a color development at 405 nm (optical density, OD405).The color development was quantified with a charge-coupled device(CCD)—camera and an image processing system.

The OD405-values obtained by a CCD-camera was considered as raw datavalues (“rampo values,” “rampo units,” or “rampo scores”). The valuesmostly ranged from 0 to 3000, a log scale similar to 1 to 3 of astandard 96-well plate ELISA-reader. First the CCD-camera made a pictureof the card before peroxidase coloring and then again a picture afterthe peroxidase coloring. These two pictures were subtracted from eachother, which resulted in the data which was considered raw data. Thesevalues were copied into an excel file and labeled as a raw data file.One follow-up manipulation was allowed. Sometimes a well can contain anair-bubble resulting in a false-positive value. If manual inspection ofthe cards detect an air-bubble the value are set to 0 for that well.

A library of peptides tested for binding to peptide P3028 included allsubstitutions for each position of the peptide P28R (SEQ ID NO: 2)(i.e., 19 substitutions for each position). The results of the bindingexperiments are shown in FIGS. 27, 28, 29 and 30 and Table 5.1. Ramposcores ranged between 102 and 1190 for all substitutions in each of the16 positions of P28R. P28R had rampo values ranging between 262 and 460with a mean value of 370. As shown in FIG. 28, 31 single-amino acidsubstitutions of the peptide P28R (SEQ ID NO: 2) had a rampo score above500. These 31 substituted peptides include SEQ ID NOs: 3-31, and areshown in Table 6.1. Significant higher values were observed for thesubstitutions M, Q, H, N in position 13 (SEQ ID NOs: 22 to 25,respectively), all with values above 800. In addition, M and S inposition 7 (SEQ ID NOs: 9 and 10, respectively), and Q and M in position11 (SEQ ID NOs: 15 and 16, respectively) all have rampo values over 700.

TABLE 6.1 Peptides that bind to P3028 with a rampo score above 500SEQ ID NO Sequence 3 RKLDTFFVKLSLFTER 4 KKGDTFFVKLSLFTER 5KKEDTFFVKLSLFTER 6 KKLDQFFVKLSLFTER 7 KKLDTAFVKLSLFTER 8KKLDTVFVKLSLFTER 9 KKLDTFMVKLSLFTER 10 KKLDTFSVKLSLFTER 11KKLDTFVVKLSLFTER 12 KKLDTFTVKLSLFTER 13 KKLDTFLVKLSLFTER 14KKLDTFFVKVSLFTER 15 KKLDTFFVKLQLFTER 16 KKLDTFFVKLMLFTER 17KKLDTFFVKLTLFTER 18 KKLDTFFVKLHLFTER 19 KKLDTFFVKLSQFTER 20KKLDTFFVKLSVFTER 21 KKLDTFFVKLSMFTER 22 KKLDTFFVKLSLMTER 23KKLDTFFVKLSLQTER 24 KKLDTFFVKLSLHTER 25 KKLDTFFVKLSLNTER 26KKLDTFFVKLSLPTER 27 KKLDTFFVKLSLSTER 28 KKLDTFFVKLSLGTER 29KKLDTFFVKLSLATER 30 KKLDTFFVKLSLRTER 31 KKLDTFFVKLSLFNER 32KKLDTFFVKLSLFPER 33 KKLDTFFVKLSLFRER

For each position of P28R, the rampo scores of the group of 19 differentpeptides containing an L-amino acid substitution were compared to therampo score of a control sample P28R peptide (SEQ ID NO: 2) for thatgroup. Single-amino acid substitutions having a rampo score greater thanor substantially equivalent to P28R were identified. As used herein, arampo score “substantially equivalent to P28R” is a rampo score that isat least 98% of the rampo score of P28R. Thus, variants of P28R havingequivalent or better binding to P3028 were identified.

For example, at position 8 of P28R (SEQ ID NO: 2) is a V. The controlsample P28R peptide had a rampo score of 308, and peptides having an F,G, L, P or R at position 8 (SEQ ID NOs: 326-330, respectively) each hada rampo score greater than or equal to 302 (98% of 308). The singleamino acid substitutions of P28R having a score greater than or equal tothat of the P28R control sample peptide for that group are shown inTable 6.2.

TABLE 6.2 Peptides that bind to a rampo scoregreater than or substantially equivalent to that of P28R SEQRampo score of ID Rampo P28R control NO Position Sequence Score sample268 1 AKLDTFFVKLSLFTER  466 308 269 1 DKLDTFFVKLSLFTER  373 308 270 1EKLDTFFVKLSLFTER  396 308 271 1 GKLDTFFVKLSLFTER  367 308 272 1HKLDTFFVKLSLFTER  428 308 273 1 IKLDTFFVKLSLFTER  483 308 274 1LKLDTFFVKLSLFTER  449 308 275 1 MKLDTFFVKLSLFTER  457 308 276 1NKLDTFFVKLSLFTER  445 308 277 1 PKLDTFFVKLSLFTER  387 308 278 1QKLDTFFVKLSLFTER  455 308 279 1 RKLDTFFVKLSLFTER  523 308 280 1TKLDTFFVKLSLFTER  493 308 281 1 VKLDTFFVKLSLFTER  442 308 282 3KKADTFFVKLSLFTER  427 375 283 3 KKCDTFFVKLSLFTER  432 375 284 3KKDDTFFVKLSLFTER  492 375 285 3 KKEDTFFVKLSLFTER  528 375 286 3KKFDTFFVKLSLFTER  393 375 287 3 KKGDTFFVKLSLFTER  563 375 288 3KKHDTFFVKLSLFTER  477 375 289 3 KKIDTFFVKLSLFTER  454 375 290 3KKKDTFFVKLSLFTER  386 375 291 3 KKMDTFFVKLSLFTER  460 375 292 3KKNDTFFVKLSLFTER  374 375 293 3 KKQDTFFVKLSLFTER  473 375 294 3KKRDTFFVKLSLFTER  370 375 295 3 KKSDTFFVKLSLFTER  393 375 296 3KKTDTFFVKLSLFTER  451 375 297 3 KKVDTFFVKLSLFTER  377 375 298 4KKLATFFVKLSLFTER  494 414 299 4 KKLETFFVKLSLFTER  417 414 300 4KKLITFFVKLSLFTER  430 414 301 4 KKLVTFFVKLSLFTER  424 414 302 4KKLWTFFVKLSLFTER  443 414 303 4 KKLYTFFVKLSLFTER  422 414 304 5KKLDCFFVKLSLFTER  449 424 305 5 KKLDMFFVKLSLFTER  475 424 306 5KKLDNFFVKLSLFTER  436 424 307 5 KKLDPFFVKLSLFTER  427 424 308 5KKLDQFFVKLSLFTER  535 424 309 5 KKLDRFFVKLSLFTER  430 424 310 5KKLDSFFVKLSLFTER  458 424 311 5 KKLDWFFVKLSLFTER  418 424 312 5KKLDYFFVKLSLFTER  425 424 313 6 KKLDTAFVKLSLFTER  575 437 314 6KKLDTIFVKLSLFTER  466 437 315 6 KKLDTMFVKLSLFTER  467 437 316 6KKLDTNFVKLSLFTER  446 437 317 6 KKLDTPFVKLSLFTER  497 437 318 6KKLDTTFVKLSLFTER  481 437 319 6 KKLDTVFVKLSLFTER  547 437 320 7KKLDTFLVKLSLFTER  517 460 321 7 KKLDTFMVKLSLFTER  712 460 322 7KKLDTFQVKLSLFTER  511 460 323 7 KKLDTFSVKLSLFTER  700 460 324 7KKLDTFTVKLSLFTER  517 460 325 7 KKLDTFVVKLSLFTER  527 460 326 8KKLDTFFFKLSLFTER  358 308 327 8 KKLDTFFGKLSLFTER  379 308 328 8KKLDTFFLKLSLFTER  411 308 329 8 KKLDTFFPKLSLFTER  456 308 330 8KKLDTFFRKLSLFTER  365 308 331 9 KKLDTFFVRLSLFTER  374 377 332 10KKLDTFFVKASLFTER  426 348 333 10 KKLDTFFVKFSLFTER  403 348 334 10KKLDTFFVKGSLFTER  495 348 335 10 KKLDTFFVKISLFTER  415 348 336 10KKLDTFFVKMSLFTER  460 348 337 10 KKLDTFFVKNSLFTER  365 348 338 10KKLDTFFVKPSLFTER  436 348 339 10 KKLDTFFVKQSLFTER  470 348 340 10KKLDTFFVKRSLFTER  439 348 341 10 KKLDTFFVKSSLFTER  351 348 342 10KKLDTFFVKTSLFTER  399 348 343 10 KKLDTFFVKVSLFTER  658 348 344 10KKLDTFFVKYSLFTER  382 348 345 11 KKLDTFFVKLHLFTER  535 442 346 11KKLDTFFVKLMLFTER  744 442 347 11 KKLDTFFVKLNLFTER  451 442 348 11KKLDTFFVKLQLFTER  768 442 349 11 KKLDTFFVKLTLFTER  520 442 350 12KKLDTFFVKLSAFTER  462 428 351 12 KKLDTFFVKLSHFTER  460 428 352 12KKLDTFFVKLSIFTER  456 428 353 12 KKLDTFFVKLSMFTER  499 428 354 12KKLDTFFVKLSNFTER  462 428 355 12 KKLDTFFVKLSQFTER  651 428 356 12KKLDTFFVKLSRFTER  483 428 357 12 KKLDTFFVKLSSFTER  478 428 358 12KKLDTFFVKLSTFTER  437 428 359 12 KKLDTFFVKLSVFTER  545 428 360 12KKLDTFFVKLSWFTER  409 428 361 13 KKLDTFFVKLSLATER  525 402 362 13KKLDTFFVKLSLCTER  400 402 363 13 KKLDTFFVKLSLGTER  531 402 364 13KKLDTFFVKLSLHTER 1046 402 365 13 KKLDTFFVKLSLITER  468 402 366 13KKLDTFFVKLSLLTER  448 402 367 13 KKLDTFFVKLSLMTER 1190 402 368 13KKLDTFFVKLSLNTER  862 402 369 13 KKLDTFFVKLSLPTER  696 402 370 13KKLDTFFVKLSLQTER 1144 402 371 13 KKLDTFFVKLSLRTER  502 402 372 13KKLDTFFVKLSLSTER  635 402 373 13 KKLDTFFVKLSLTTER  494 402 374 13KKLDTFFVKLSLVTER  446 402 375 13 KKLDTFFVKLSLWTER  430 402 376 14KKLDTFFVKLSLFFER  348 319 377 14 KKLDTFFVKLSLFGER  343 319 378 14KKLDTFFVKLSLFHER  463 319 379 14 KKLDTFFVKLSLFIER  375 319 380 14KKLDTFFVKLSLFLER  360 319 381 14 KKLDTFFVKLSLFMER  501 319 382 14KKLDTFFVKLSLFNER  599 319 383 14 KKLDTFFVKLSLFPER  551 319 384 14KKLDTFFVKLSLFSER  369 319 385 14 KKLDTFFVKLSLFVER  380 319 386 14KKLDTFFVKLSLFWER  374 319 387 15 KKLDTFFVKLSLFTDR  404 371 388 16KKLDTFFVKLSLFTEF  297 260 389 16 KKLDTFFVKLSLFTEK  291 260 390 16KKLDTFFVKLSLFTEN  311 260 391 16 KKLDTFFVKLSLFTER  260 260 392 16KKLDTFFVKLSLFTET  292 260 393 16 KKLDTFFVKLSLFTEY  311 260

The positional substitutions of P28R in Table 6.2, (SEQ ID NOs: 268-393)are summarized in FIG. 32. It is noted that positions 2 (K), 9 (K) and15 (E) tolerate relatively few substitutions while still binding toP3028. Substitution of the residue at positions 2, 9, and/or 15 of P28Rcan result in binding to P3028 (as measured by rampo scores)substantially lower than unsubstituted P28R. Thus, it is contemplatedherein that these 3 positions appear to modulate signal transduction.One skilled in the art will appreciate that signal transductionmodulatory activity of these positions can be useful in designinginhibitors of immunomodulatory peptides.

PEPSCAN analysis was also performed on truncations and internaldeletions of peptide P28R. Shown in FIG. 29 are rampo scores forpeptides having the sequences KKLDTFFVKLSLFTER (SEQ ID NO: 2);KKLDTFFVKLSLFTE (SEQ ID NO 34); KKLDTFFVKLSLFT (SEQ ID NO: 35);KKLDTFFVKLSLF (SEQ ID NO 36); KKLDTFFVKLSL (SEQ ID NO: 37); KKLDTFFVKLS(SEQ ID NO: 38); KKLDTFFVKL (SEQ ID NO: 39); KKLDTFFVK (SEQ ID NO: 40);KKLDTFFV (SEQ ID NO: 41); KKLDTFF (SEQ ID NO: 42); KKLDTF (SEQ ID NO:43); KKLDT (SEQ ID NO: 44); KKLD (SEQ ID NO: 45); KLDTFFVKLSLFTER (SEQID NO: 46); LDTFFVKLSLFTER (SEQ ID NO: 47); DTFFVKLSLFTER (SEQ ID NO:48); TFFVKLSLFTER (SEQ ID NO: 49); FFVKLSLFTER (SEQ ID NO: 50);FVKLSLFTER (SEQ ID NO:51); VKLSLFTER (SEQ ID NO: 52); KLSLFTER (SEQ IDNO: 53); LSLFTER (SEQ ID NO: 54); SLFTER (SEQ ID NO: 55); LFTER (SEQ IDNO: 56); FTER (SEQ ID NO: 57); KLDTFFVKLSLFTE (SEQ ID NO: 58);LDTFFVKLSLFT (SEQ ID NO: 59); DTFFVKLSLF (SEQ ID NO: 60); TFFVKLSL (SEQID NO: 61); FFVKLS (SEQ ID NO: 62); FVKL (SEQ ID NO: 63).

Shown in FIG. 30 are rampo scores for peptides having the sequencesKKLDTFFVKLSLFTER (SEQ ID NO: 2); KLDTFFVKLSLFTER (SEQ ID NO: 46);KKLTFFVKLSLFTER (SEQ ID NO: 64); KKLDTFVKLSLFTER (SEQ ID NO: 65);KKLDTFFKLSLFTER (SEQ ID NO: 66); KKLDTFFVKSLFTER (SEQ ID NO: 67);KKLDTFFVKLSFTER (SEQ ID NO: 68); KLDTFFVKLSLFER (SEQ ID NO: 69);KLDTFFVKLSLFTE (SEQ ID NO: 58); LDTFFVKLSLFTER (SEQ ID NO: 47);KKTFFVKLSLFTER (SEQ ID NO: 70); KKLDFVKLSLFTER (SEQ ID NO: 71);KKLDTEKLSLFTER (SEQ ID NO: 72); KKLDTFFVSLFTER (SEQ ID NO:73);KKLDTFFVKLFTER (SEQ ID NO: 74); KKLDTFFVKLSLER (SEQ ID NO: 75);LDTFFVKLSLFT (SEQ ID NO: 59); DTFFVKLSLFTER (SEQ ID NO: 48);KKFFVKLSLFTER (SEQ ID NO: 76); KKLDVKLSLFTER (SEQ ID NO: 77);KKLDTFLSLFTER (SEQ ID NO: 78); KKLDTFFVLFTER (SEQ ID NO: 79);KKLDTFFVKLTER (SEQ ID NO: 80); KKLDTFFVKLSLR (SEQ ID NO: 81);KFFVKLSLFTER (SEQ ID NO: 82); KKLVKLSLFTER (SEQ ID NO: 83); KKLDTLSLFTER(SEQ ID NO: 84); KKLDTFFLFTER (SEQ ID NO: 85); KKLDTFFVKTER (SEQ ID NO:86); KKLDTFFVKLSR (SEQ ID NO: 87); KFVKLSLFTER (SEQ ID NO: 88);KKLKLSLFTER (SEQ ID NO: 89); KKLDTSLFTER (SEQ ID NO:90); KKLDTFFFTER(SEQ ID NO: 91); KKLDTFFVKER (SEQ ID NO: 92); KKLDTFFVKLS (SEQ ID NO:38); GKLDTFFVKLSLFTER (SEQ ID NO: 93); KKGDTFFVKLSLFTER (SEQ ID NO: 94);KKLDGFFVKLSLFTER (SEQ ID NO: 95); KKLDTFGVKLSLFTER (SEQ ID NO: 96);KKLDTFFVGLSLFTER (SEQ ID NO: 97); KKLDTFFVGLSLFTER (SEQ ID NO: 98);KKLDTFFVKLGLFTER (SEQ ID NO: 99); KKLDTFFVKLSLGTER (SEQ ID NO: 100);KKLDTFFVKLSLFTGR (SEQ ID NO: 101).

As shown in FIG. 30, several deletions and truncations of peptide P28Rhave a rampo score comparable to, or higher than peptide P28R, includingpeptides of the sequences SEQ ID NOs: 64, 65, 68, and 76. Additionallyseveral glycine substitutions had rampo scores comparable to P28R,including peptides of SEQ ID NOs: 94, 95, 96, 98, and 99. Deleting up toat least 8 amino acids from the N terminal of P28R (SEQ ID NOs: 46 to53) retained a high affinity to P3028 as measured by rampo score.Deleting the C terminal R of P28R (SEQ ID NO: 34) retained a highaffinity to P 3028.

EXAMPLE 13 Effect of a Low Molecular Weight Inhibitor of P3028 onLymphocyte Activation

Analyses of the inhibitor of P3028, P28R, were performed in human exvivo models. The stimulatory activity on PBMCs, measured using the MTSor CFSE techniques, were studied in 7 healthy control samples and 7cancer patients of various diagnoses. Interestingly, even in the absenceof other types of stimulation P28R has a significant stimulatoryactivity in 6 out of 7 cancer patients whereas PBMCs from controlsamples showed only a weak or no stimulation.

As shown in FIG. 24, stimulatory activity of P28R on suppressedproliferative response to IL-2. PBMCs were cultured for 7 days with IL-2and the proliferative rate was determined as incorporation of BrdU. Eachbar represents mean value of triplets. Similar to the studies on theefficacy of antibodies (see FIG. 22) directed against P3028 to reversecancer related immunosuppression determined as a poor proliferativeresponse of PBMCs from cancer patients to IL-2, the efficacy of the lowmolecular weight inhibitor P28R on reversal of suppressed IL-2 inducedproliferation was investigated. The results of cultures of PBMCs fromfour different treatment naïve patients are shown in FIG. 24. For eachquantity of added P28R, IL-2 stimulated cells 240 are shown in the left,and unstimulated 242 are shown on the right. PBMCs with a low initialproliferation (see FIGS. 24A and 24B) were markedly stimulated by P28Rwhereas a high initial proliferation was essentially unaffected by thedrug (see FIGS. 24C and 24D). As expected, systemic immunosuppressionwas not present in all patients and only those with immunosuppressionwere stimulated.

EXAMPLE 14 Binding of a Low Molecular Weight Inhibitor of P3028 to TumorCells

As demonstrated herein, P3028 structures are present in tumors. Abiotinylated inhibitor of P3028, P28R, was used to further study thedistribution of 3028 structures and the binding of the inhibitor intumor tissue. Three breast cancers, two renal cell carcinomas and fourmalignant melanomas were analyzed. All investigated tumors bound theinhibitor. An example of a stained breast cancer is shown in FIG. 25,and a strong positive reaction 7 is seen indicating the presence of theinhibitory 3028-structure in this tumor. As the P3028-structure inhibitslymphocyte migration as well as cytotoxic activity (described above), animmune mediated attack against positively staining tumor areas can beefficiently suppressed as long as exposed P3028 is not blocked bybinding P28R. However, lymphocytes were not stained by this proceduresince the P3028 structure was blocked by binding to LFA-1 on thesecells.

EXAMPLE 15 Unblocking the LFA-1 Receptor by P28R

As described herein, β2-integrins play a role in the normal function ofthe immune system. Also described herein are immunosuppressor mechanismsbased on the binding of an endogenous inhibitor, P3028, to theβ2-integrin LFA-1. As described in Example 7, the membrane staining ofPBMCs from cancer patients is markedly decreased compared to normalcontrol samples. The exposure of LFA-1 could, however, be enhanced byincubating PBMCs from cancer patients with an antibody directed againstthe inhibitor P3028 (see Example 7 and FIG. 16). Staining for LFA-1 wasperformed using anti-LFA-1 antibody of Example 7 and a secondaryantibody (Ultravision) followed by development with Fast Red. Freshfrozen tumor sections without any fixation were incubated for 4-20 hourswith the drug candidate, P28R before staining for LFA-1 (see FIG. 26B).For comparison, control sample tumor sections were incubated withphosphate buffered saline only (see FIG. 26A).

As is shown in FIG. 26, P28R unblocked LFA-1, and thereby markedlyenhanced the functional expression of LFA-1 enabling migration andcytotoxic activity of these cells. Strong LFA-1 staining 3 inP28R-treated cells is contrasted with weak LFA-1 staining 5 in untreatedcells. These results show that LFA-1 was unblocked by removal of theP3028 structure by the P28R.

EXAMPLE 16 Delivery of Immunoregulatory Peptide Inhibitors ViaNanodosing to Cancer Patients

Cancer patients with immunosuppression due to the presence of P3028structures and having subcutaneous melanoma metastases are selected. Amicro-dialysis catheter is inserted into one of these metastases afterthe inflammatory infiltrate has been determined using a fine needlebiopsy. The base line: inflammatory infiltrate, cytokine profile andconcentration of P3028 structures are determined before infusion of theP3028-specific immunoregulatory peptide inhibitor. Changes of thecytokine profile and concentration of P3028 structures are thendetermined during and after the infusion. The infusion will continue for24 or 48 hours and the area supplied by the micro-dialysis catheter willbe excised immediately after the infusion and then after one and twoweeks in order to study the inflammatory infiltrate and tumor regressivechanges. It is expected that the administration of the immunoregulatorypeptide inhibitor will reduce the immunosuppression of the cancerpatient, as measured, for example, by de-blocking LFA-1, binding P3028structures, and/or enhancing immune cell recruitment.

EXAMPLE 17 Albumin Peptide Binders of Cell Surface Molecules

Albumin Fragments that Bind to Cell Surface Molecules

As taught in US Publication No: 2011/0262470 (hereby expresslyincorporated by reference in its entirety) some albumin fragments canbind to cell surface molecules. U.S. Publication No: 2011/0262470reports the identification of serum peptides that bind to ArtificialCell Surface (ACS) columns. The ACS columns were prepared as follows:

First, biotinylated cell surface proteins were prepared. Buffy coatsgenerated from 450 ml blood each were collected from 4 healthy donors.Erythrocytes were removed by sedimentation on 2% dextran T500 solution(Amersham Pharmacia Biotech AB, Uppsala Sweden) in 0.9% NaCl.Mononuclear cells (PBMC) were then isolated by Ficoll-Paque Plus (GEHealthcare BioscienceAB Sweden) density gradient centrifugation. ThePBMCs were then suspended in phosphate buffered saline (PBS) containingCa and Mg (GIBCO) at a concentration of 10×106/ml. EZ LinkSulfo-NHS-biotin (Pierce USA) was added at a final concentration of 0.2mg/ml and the mixture incubated on a shaker at room temperature for 10min. Excess biotin was then removed by washing the PBMC in PBS.Biotinylated PBMC were then lysed by adding 1.0 ml ice-cold lysingbuffer (50 mM Tris-HCL, pH 7.5, with 0.15 MNaCl, 5 mM MgCI2 containing100 mM Octyl glucoside and 1 mM Phenylmethylsulfonyl fluoride) per 2×10⁷pelleted cells with gentle shaking, then incubated for 30 min. on ice.Debris was removed by centrifugation at 5000×g at 4° C. for 10 min andthe supernatants were collected and pooled from all four donors. Thelysate was then stored at −70° C. in polypropylene plastic tubes.

To study the absorptions by trypsin-fragment dHSA, affinity columns withbiotinylated cell surface proteins from mononuclear cells coupled tostreptavidin-sepharose were prepared as follows: 18 ml biotinylated celllysate in lysate buffer was diluted 1/10 in binding buffer (20 mMNaH2PO4, 0.15 M NaCI, pH 7.5). This amount of lysate corresponds to36×10⁷ mononuclear cells. It was added to a 1 ml Hitrap Streptavidin HPaffinity column (Amersham Biosciences). To block possible remaining freebiotin, 5 ml of 0.1 M glycine (Sigma) was added to the column.Unsaturated streptavidin on the column was then reacted with 150 ugbiotin (Sigma) in binding buffer. The column was carefully washed withPBS and stored in PBS with 0.1% NaN3 at 4° C. until use.

To study the absorptions by of ASP-N fragmented dHSA, affinity columnswith biotinylated cell surface proteins from mononuclear cells coupledto streptavidin-sepharose were prepared as follows: Biotinylated celllysate in lysate buffer underwent buffer exchange by dialysis withSpectrapore 4 dialysis tubing (Spectrum Europe, Breda, The Netherlands)in binding buffer (20 mM NaH2PO4, 0.15 MNaCI pH 7.5). 27 ml biotinylatedcell lysate in binding buffer (corresponding to 54×10⁷ mononuclearcells) was added to 1.5 ml washed Streptavidin Sepharose HP (AmershamBiosciences). To block possible remaining free biotin, 25 ml of 0.1 Mglycine (Sigma) was added to the Streptavidin Sepharose. Unsaturatedstreptavidin was then reacted with 225 ug biotin (Sigma) in bindingbuffer. The Streptavidin Sepharose was carefully washed in PBS. One mlof the biotinylated cell lysate coupled Streptavidin Sepharose was thenpacked in an empty column (Tricorn Empty High Performance Column,Amersham Bioscience) and washed with phosphate buffered saline (PBS)containing Ca²⁺ and Mg²⁺ (GIBCO).

Digestion with trypsin or ASP-N was performed as follows. Freeze drieddHSA (0.5 mg) was reconstituted in 25 mM NH4HCO3, pH 8, containing 10 mgsequencing grade modified trypsin (Promega Corporation, WI) or 2 mgEndoproteinase ASP-N(Sigma) and incubated at 37° C. overnight. To removeunfragmented albumin and enzyme, the sample was ultra filtered throughan Amicon Ultra 4 (mw cut-off of 5000) or a Centriplus (mw cut-off10000) centrifugal filter (Millipore AB, Solna, Sweden). The filtrate,containing fragmented dHSA without enzymes, was collected and dilutedwith PBS with Ca and Mg (GIBCO).

dHSA was trypsinated, and the mixture of peptides obtained aftertrypsination was adsorbed by ACS. Two ml of enzyme-fragmented dHSA inPBS, corresponding to a total of 0.2 mg protein, was passaged over theACS column. The flow-through was collected with consideration taken tovoid volume and dilution of adsorbed sample by collecting in smallportions of 0.2 ml. Thirty microliters of each sample, including acontrol sample that has not been adsorbed, were dried in a Speed-Vaccentrifuge. The binding peptides were identified by comparing adsorbedand unadsorbed peptide solutions using the MALDI TOF mass spectrometrytechnique. Dried samples were reconstituted in 10 ul of 0.1% TFA. ZipTip pipette tips (Millipore, USA) containing C18 reversed-phase mediawere used for desalting reconstituted samples. For analysis of samplesin the mass range 700-3600 Da, one μl of each Zip Tip eluted sample wasmixed with 1 μl of a saturated solution of α-cyano-4-hydroxycinamic acid(0.02 mg/ml) in 70% acetonitrile/0.3% trifluoro acetic acid. For theanalysis of samples in the mass range 1500-9000 Da, one al of each ZipTip eluted sample was mixed with 1 μl of sinapinic acid(3-methoxy-4-hydroxycinnamic acid). 1 μl of the mixture was spotted onthe MALDI plate and analysed using MALDI-TOF MS (Voyager-DE PRO, AppliedBiosystems, CA, US). Mass identity search of resulting spectra wasperformed in the SwissProt or NCBI databases using MS-Fit.

These peptides are shown in Table 7.

TABLE 7 Trypsin-generated albumin fragments that bind to ACS PercentAlbumin SEQ ID NO: Absorbed Sequence Positions 194 71% KYLYEIAR 161-168195 64% KVPQVSTPTLVEVSR 438-452 196 60% VFDEFKPLVEEPQNLIK 397-413 19759% VPQVSTPTLVEVSR 439-452 198 42% RPCFSALEVDETYVPK 509-524 199 41%FQNALLVR 427-434 200 36% SLHTLFGDK 89-97 201 36% LKECCEKPLLEK 299-310202 35% LCTVATLR  98-105 203 34% YLYEIAR 162-168 204 32% CCAAADPHECYAK384-396 205 29% AAFTECCQAADK 187-198 206 26% CCTESLVNR 500-508 207 25%QEPERNECFLQHK 118-130 208 23% AVMDDFAAFVEK 570-581 209 22% NECFLQHK123-130 210 20% ONCELFEQLGEYK 414-426 211 18% QEPERNECFLQHK 118-130 21213% VHTECCHGDLLECADDR 265-281 213  8% FKDLGEENFK 35-44 214  3%YICENQDSISSK 287-298 215  2% LDELRDEGK 206-214 216  1% DDNPNLPR 131-138

Because the full peptide sequence of albumin is not recovered using theMALDI-TOF technique after trypsin degradation, and because somesequences with the capacity to bind to cell surface receptors of immunecells, might have been degraded by trypsin treatment, dHSA was alsodegraded by asparaginase (ASN-N), and the mixture of peptides obtainedafter degradation was adsorbed by ACS. The binding peptides wereidentified by comparing adsorbed and unadsorbed peptide solutions usingthe MALDI TOF ms technique. These peptides are shown in Table 8.

TABLE 8 Asp-N-generated albumin fragments that bind to ACS SEQ IDPercent Albumin NO: Absorbed Sequence Positions 217 100%DHVKLVNEVTEFAKTCVA 62-79 218 100% DDKETCFAEEGKKLVAASQAALGL 586-609 219 87% DRVTKCCTESLVNRRPCFSALEV 495-517 220  86% DETYVPKEFNAETFTHA 518-535221  65% DSISSKLKECCEKPLLEKSHCIA 293-319 EVEN 222  65% DKLCTVATLRETYGEM 96-112 223 100% YSVVLLLRLAKTYETTLEKCCAAAD 364-398 PHECYAKVF 224 100%KLCTVATLRETYGEMADCCAKQE  96-130 PERNECFLQHK 225 100%ICTLSEKERQIKKQTALVELVKHK 536-572 PKATKEQLKAVM 226 100%LAKYICENQDSISSKLKECCEKPLL 283-319 EKHCIAEVEN 227 100%VFLGMFLYEYARRHPDYSVVLLLR 348-388 LAKTYETT LEKCCAAA 228 100%LGEENFKALVLIAFAQYLQQCPFE 37-79 DHVKLVNEVTEFAKTCVA 229 100%RVTKCCTESLVNRRPCFSALEVDE 495-535 TYVPKEFNAETFTFHA 230  37%YLSVVLNQLCVLHEKTPVSDRVTK 475-517 CCCTESLVNRRPFSALEV

Additionally, nine synthetic albumin peptides were synthesized, as shownin Table 9.

TABLE 9 Synthetic albumin peptides SEQ Peptide Albumin ID NO: NameSequence Positions 183 3026 NEETFLKKYLYEIARRHPYFYAP 153-176 184 3027ELFEQLGEYKFQNALLVR 417-434 185 3028 VFDEFKPLVEEPQNLIK 397-413 188 3029KVPQVSTPTLVEVSR 438-452 189 2604 KLVNEVTEFAKT 65-76 190 2605NEETFLKKYLYE 153-168 191 2606 LDELRDEGKAS 205-217 192 2607 EMADCCAKQEPE110-122 193 2608 ELFEQLGEYKF 417-427

EXAMPLE 18 Albumin Peptide Binders of Cell Surface Molecules

Monoclonal antibody mAb A was shown to have immunomodulatory activity.Structures of the epitope bound by mAb A were further investigated.Briefly, albumin fragments were incubated with antibody, andMatrix-Assisted Laser Desorption/Ionisation Time-of-Flight massspectrometry (MALDI-TOF ms) were used in order to define the possiblesite or sites on human serum albumin to which a mouse monoclonalantibody specific for denatured albumin binds. One approach tookadvantage of the fact that some tryptic peptides to which an antibody isbound will not generate characteristic mass spectra in MALDI as they are“hidden” from the analysis. Another approach takes advantage of the factthat sites on a protein where an antibody has bound are protected fromproteolysis.

Purified human serum albumin (HSA) was denatured with urea, reduced withDTT and alkylated. The denatured HSA was then subjected to trypsintreatment with a low concentration (0.02-2 ng/ml) of trypsin. However,the spectra obtained with MALDI were unsatisfactory, as the peptidesmasses typical for albumin were not found. Based on gel electrophoresisthis preparation (digested by 0.02 ng/ml of trypsin) was found tocontain substantial amounts of undigested albumin. Therefore, trypsindigestion was continued, at a higher concentration (5 ug/ml) in order toobtain the mass spectra usually used for identification of proteins byMALDI.

To identify albumin fragments bound by mAb A, some of the now completelycleaved albumin solution was incubated with the mAb A. MALDI-TOF ms wasperformed and spectra of enzyme-treated denatured albumin obtained inthe presence or absence of mAb A were compared. Fourteen albumin (SEQ IDNOs: 231-244) massed were absent or reduced after incubation with mAb A.The amino acid sequence of these peptides is shown in Table 10. Thespectra represent multiple areas encompassing residues 66 to 508 of thealbumin molecule.

In order to further confirm these results the monoclonal antibody mAb Awas allowed to bind to the denatured albumin (previously digested bytrypsin at a concentration of 0.02 ng/ml) in order to protect thepeptide sequences of the epitope. The complex was then again treatedwith trypsin. MALDI-TOF ms was then performed and the peptide massspectra generated from albumin were compared with spectra generated fromdenatured albumin trypsin-treated in the absence of antibody. The samefourteen masses out of 39 albumin masses disappeared completely or weresignificantly reduced in the sample were the mAb was present duringtrypsin treatment (see Table 10, Column 6). Multiple readings were takento verify the results.

TABLE 10 Albumin peptides that bind to monoclonal antibody mAb APeak area Peak area Peak area SEQ before after trypsiniated ID AlbuminAb incub. Ab incub. Albumin + Ab NO: Sequence Positions (2 spectra)(5 spectra) (6 spectra) 231 LVNEVTEFAK 066-075 1970, 4092 0, 0, 0, 0, 0,0, 0, 0, 0, 0, 0, 232 SLHTLFGDK 089-097 1695, 5089 0, 0, 0, 0, 0,0, 0, 0, 0, 0, 0, 233 LCTVATLR 098-105 1862, 4869 0, 0, 132, 0, 00, 0, 0, 0, 0, 0, 234 ETYGEMADCCAK 106-117  809, 1010 0, 0, 0, 0, 0,0, 0, 0, 0, 0, 0, 235 YLYEIAR 162-168  6036, 13066 504, 118, 473,448, 895, 216, 281, 288 724, 2346, 1571 236 LDELRDEGK 206-214 3064, 79170, 0, 0, 0, 0 0, 0, 0, 0, 0, 0 237 YICENQDSISSK 287-298  583, 13940, 0, 0, 0, 0, 0, 0, 53, 0, 0, 0, 238 LKECCEKPLLEK 299-310 2283, 46750, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 239 HPDYSVVLLLR 362-372 1036, 14820, 0, 0, 0, 0, 0, 0, 51, 0, 407 (1312), 226 (1312) 240 CCAAADPHECYAK384-396 2186, 3327 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 241 QNCELFEQLGEYK414-426 2519, 2978 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 212 (1656.64) 242FQNALLVR 427-434 15276, 32846 267, 315, 931, 591, 1284, 199, 494, 3091015, 2963, 1998 243 CCTESLVNR 500-508 1360, 4659 0, 0, 0, 0, 0,0, 258, 0, 0, 0, 204 (1139) 244 AVMDDFAAFVEK 570-581 2720, 37580, 0, 0, 0, 0 0, 0, 0, 0, 0, 0

Some peptide fragments of albumin might not be identified by binding anantibody to trypsinated fragments of albumin because of the possibilitythat the mAb binding epitope of albumin is cleaved by trypsin, resultingin fragments of the epitope with too low binding affinity to bind to themAb. Therefore, an additional method was used to identify fragmentsbound by the antibody. MALDI epitope mapping of mAb A based on antibodyprotection of proteolysis was repeated. This time a slightly differentapproach was used. Denatured HSA was incubated with mAb A. Albumin notbound by the antibody, was removed from the sample by size exclusion onan ultra filter. The remaining free mAbs and the complexes ofmAb-albumin was then digested with trypsin (sequences of the albuminmolecule to which mAb is bound should resist the trypsin digestion).Small cleaved fragments of mAb and unprotected albumin was then removedfrom the sample by ultrafiltration (30 kD). The complexes of mAb andbound albumin fragments were dissociated by lowering the pH to 2.7.Again ultrafiltration at 30 kD was performed to separate whole mAb fromalbumin fragments smaller than 30 kD. MALDI TOF analysis of thesefragments did not identify spectra typical for albumin. Reasonably,because the fragments containing the epitope of mAb A were still toolarge. This filtrate (<30 kD) was then further digested with trypsin(for cleavage of sites previously protected by the mAb) in order togenerate peptide masses suitable for analysis with MALDI TOF ms.

After this second trypsin treatment, eight of 32 masses detected byMALDI TOF ms matched to albumin (see Table 11). Thus, these new aminoacid sequences represent a part of the epitope, which also containssequences on the other side of the trypsin cleavage point. Six of theeight peptide masses ((SEQ ID NOs: 231, 233, 235, 236, 242, and 243)were peptide masses that also disappeared when analysed previously whencompletely cleaved albumin was incubated with the mAb A before theMALDI-TOF analysis (see Table 10). Two of the eight peptides (SEQ IDNOs: 245 and 346) had not been identified in the binding assays withcompletely cleaved albumin. The epitope/s of this antibody was thusestablished. It is important to note that multiple such structures arepresent in the albumin molecule, which can then cause cross-linking ofthe receptors to which they are bound. However, multiple epitope sitesfor mAb A can indeed exist on albumin.

TABLE 11 Albumin peptides that bind to monoclonal antibody mAb ASEQ ID NO: Sequence Albumin Positions 245 LSQRFPK 243-249 246 DDNPNLPR131-138 235 YLYEIAR 162-168 233 LCTVATLR  98-105 242 FQNALLVR 427-434236 LDELRDEGK 206-214 243 CCTESLVNR 500-508 231 LVNEVTEFAK 66-75

EXAMPLE 19 Cyclic Peptides that Bind P3028

In order to identify cyclic peptides that bind to P3028, all possiblevariants of di- and tripeptides were synthesized on chips and thebinding of the His-tag labeled P 3028 was analyzed using theELISA-technique. Based on the identified binding motifs, looped 6-mereswere produced and tested. These results together enable the constructionof a lead cyclic peptide CLALNVMCG (SEQ ID NO: 264). Positional scanswere performed in each position of the lead cyclic peptide was replacedwith each of the other 19 L-amino acids. Binding of each of thesubstituted peptides was tested, and peptide sequences with even betterbinding capacity than that of the lead peptide were identified. The twopeptides with the highest affinity were CLRLNVFCG (SEQ ID NO: 265) andCLRLIVMCG (SEQ ID NO: 266). The two best looped peptides that bind toP3028 based on the positional scan binding assay are summarized in Table12.

TABLE 12 Cyclic peptides that bind to P3028 SEQ ID NO: SEQUENCE 264CLALNVMCG 265 CLRLNVFCG 266 CLRLIVMCG

Substitutable amino acid residues in the lead looped peptide that wereidentified in the positional scans as providing improved binding toP3028 (SEQ ID NO: 185) are summarized in FIG. 33 (i.e., SEQ ID NOs: 264to 266). Positional substitutions of P28R that result in equivalent orbetter binding to P28R to P3028 that were identified as providing higheror substantially equal binding to P3028 (see Tables 6.1 and 6.2) arealso summarized in FIG. 33. It was observed that there was very goodhomology between looped peptide sequences that bind to P3028 based onthe scan data (SEQ ID NOs: 264-266), and sequences of linear peptidesthat identified as binding to P3028 (SEQ ID NOs: 2-31 and 268-393) (seeFIG. 33). It is noted that the N-terminal C residues and C-terminal CGresidues of the cyclic peptides are involved in cyclization of thepeptide. Thus, as shown by shaded boxes in FIG. 33, there is stronghomology between 6-mere cyclic peptides identified as binders of P3028(SEQ ID NOs: 264-266) and either the N terminus of C-terminus ofP28R-related peptide (SEQ ID NOs: 2-31 and 268-393). It is contemplatedthat additional cyclic peptides that bind to and inhibit albumin-derivedimmunoregulatory peptides can be identified.

EXAMPLE 20 Effect of Albumin Peptides on IL-2 Induced Proliferation

The effect of albumin peptides including at least one of SEQ ID NOs:183-185 or 188-246 is determined using the ex vivo human model asdescribed in Example 2.

PBMCs are isolated from venous blood samples from healthy blood donors(control samples) or cancer patients. One hundred pI of culture medium(RPMI 1640 Dutch's modification (Gibco, InVitrogenAB, Stockholm, Sweden)supplemented with 200 IV/ml penicillin, 200 ul/rnl streptomycin, 4 mML-glutamine (all from Sigma Chemical Co. MO, US) and 20%heat-inactivated human serum) is added to roundbottomed, 96-well tissueculture plates (Costar, Corning Inc. NY, US). For experimental cultures,the culture medium of each well is supplemented with a peptide of SEQ IDNOs: 183-185 or 188-246. One hundred pI of PBMCs in RPMI/2% HAS (5×104lymphocytes) is then added per well followed by IL-2 (Proleukin, Chiron,NL) at a final concentration of 120 IU/well. Control wells without IL-2are set up in parallel. Cells are cultured for 7 days in a humidified,5% CO2-atmosphere at 37° C. Cell proliferation is assayed byincorporation of 1.6 pCi/well of [³H]-thymidine (Amersham Int., UK)during the last 18-24 h hrs. Mean values of dpm (disintegrations perminute) of triplicate wells are used for the calculations.

Thus, albumin peptides that inhibit IL-2 stimulation of PBMC's areidentified.

EXAMPLE 21 Effect of Albumin Peptides on T Cell Receptor Stimulation

The effect of albumin peptides including at least one of SEQ ID NOs:183-185 or 188-246 on T Cell receptor stimulation is determined as inExample 3. Cells are stimulated in cultures on plates pre-coated with amonoclonal antibody directed against CD3 and the number of metabolicallyactive cells (i.e., cell proliferation) is determined using MTS stainingafter 3 to 7 days of culture. Detection of solid phase CD3 monoclonalantibody is used as a measurement of T cell proliferation.

Thus, albumin peptides that inhibit T cell receptor stimulation areidentified.

EXAMPLE 22 Effect of Albumin Peptides on NK Cell Cytotoxicity

The effect of albumin peptides including at least one of SEQ ID NOs:183-185 or 188-246 on NK cell cytotoxicity is determined as in Example4.

Mononuclear cells are separated by standard Ficoll-paque Plus (PharmaciaAB, Sweden) density gradient centrifugation from heparinized bloodobtained from healthy donors. NK cell cytotoxic activity of themononuclear cells is then tested using a commercial kit (NKTEST, OrpegenPharma GmblI, Heidelberg, Germany) following the manufacturers protocol.Briefly, the kit contains cryopreserved, NK-sensitive target cells(K562) labeled with a lipophilic green fluorescent membrane dye, whichenables discrimination of effector and target cells. After incubationwith effector cells, killed target cells are identified by a DNA-stain,which penetrates and specifically stain the nuclei of dead target cells.This way the percentage of killed targets can be determined by flowcytometry. The mononuclear cells were preincubated for 30 min at 37° C.with the indicated peptides (peptides have been described previously) at10 ug/ml. Target cells were then added, giving an effector:target ratioof 40:1, and the cell mixture incubated at 37° C. for 3-4 hours. Samplesare analysed on a FACSCalibur (BD Biosciences, San Jose, Calif.).

Thus, albumin peptides that inhibit NK cell cytotoxicity are identified.

EXAMPLE 23 Effect of Albumin Peptides on Leukocyte Spreading

The effect of albumin peptides including at least one SEQ ID NOs:183-185 or 188-246 on leukocyte spreading is determined as in Example 5.Buffy coat cells are prepared from heparinized blood by Dextran assistedsedimentation. To test the effects of each peptide, a samples of cellsare treated with of one of the peptides of (SEQ ID NOs: 183-185 or188-246 at a concentration of 10 μg/ml for 15 minutes efficientlyinhibited the spreading. These cells are then washed twice in PBS andtransferred to clean slides. Cells adherance to the glass surface andspreading is detected.

Thus, albumin peptides that inhibit leukocyte spreading are identified.

EXAMPLE 24 Effect of Albumin Peptides on Immune Cell Migration

The effect of albumin peptides including at least one of SEQ ID NOs:183-185 or 188-246 on immune cell migration is determined as in Example5. PBMC migration is studied using the Boyden chamber technique.Migration for PBMCs of healthy control samples and cancer patients isassessed in both the presence and absence of each of the peptides of SEQID NOs: 183-185 or 188-246. Thus, albumin peptides that inhibit immunecells migration are identified.

EXAMPLE 25 Binding of Albumin Peptides to LFA-1

The binding of albumin peptides including at least one of SEQ ID NOs:183-185 or 188-246 to LFA-1 is determined as in Example 7. A standardimmunohistochemical staining procedure is performed using acetonefixation, 10% human AB-serum for blocking, incubation with anti-LFA-1antibody and a secondary antibody (Ultravision) followed by developmentwith Fast Red. Pre-incubation with peptides added to the AB serum iseither no peptide added, or a peptide of SEQ ID NOs: 183-185 or 188-246is added.

Peptides that bind to LFA-1 prevent the binding of the antibody, thusdecreasing the amount of Fast Red staining in antibody-treated cells ascompared to untreated control samples.

EXAMPLE 26 Antibodies that Bind Albumin Peptides

Antibodies that specifically bind to peptides including at least one ofSEQ ID NOs: 183-185 or 188-246 are generated as in Example 9. Rabbitantisera directed against each of the peptides of SEQ ID NOs: 183-185 or188-246 are generated. Each peptide of SEQ ID NOs: 183-185 or 188-246 issynthesized with a cysteine added to the N-terminus end and thenconjugated with keyhole limpet hemocyanin (KLH) as a carrier protein.Polyclonal antisera is generated by repeated immunizations of rabbitswith KLH-conjugated P3028 and Freund's adjuvants. The antisera areaffinity purified by chromatography on P3028-conjugated Ultralinklodoacetyl gels (Pierce Biotechnology Inc.).

The antisera are tested for their ability to bind human serum and dHSA.Human serum commercially available for therapeutic purposes is tested,heated 10 times in order to be virus free. Thus, rabbit antisera thatspecifically binds the albumin peptide binds to dHSA and/or controlsample HSA.

The binding of the rabbit antiserum to peptides of SEQ ID NOs: 183-185or 188-246 is assayed using competition ELISA assay.

Effects of affinity purified antibodies directed against of SEQ ID NOs:183-185 or 188-246 on the proliferative response to IL-2 are examinedthe ex vivo model, using PBMCs from immunosuppressed cancer patients andnormal control samples.

Thus, antibodies that bind peptides of SEQ ID NOs: 183-185 or 188-246are identified.

EXAMPLE 27 Peptides that Bind to Albumin-Derived Peptides

Peptides that bind to peptides including at least one of SEQ ID NOs:183-185 or 188-246 are identified as in Example 10. Potential binders ofthe peptides are synthesized. For each peptide of SEQ ID NOs: 183-185 or188-246 a His-tagged peptide is contacted with the potential binders insolution, and then isolated from solution using the His tag. Binders ofeach peptide are isolated along with the peptide, and subsequentlyidentified.

Additionally, substitutions, truncations, and deletions of peptides thatbind to each of the albumin peptides are identified as in Example 12.Substitutions, truncations, and deletions are synthesized on a chip, andcontacted with the albumin peptide of one of SEQ ID NOs: 183-185 or188-246 to determine binding. The amount of bound peptide is quantifiedusing a rampo assay as in Example 12. The binders with the highest ramposcores are isolated.

The highest-score binders of each peptide are assessed for their abilityto reduce immunosuppression, as in Examples 13 and 15. Each binder isassessed for its ability to induce lymphocyte activation, and unblockthe LFA-1 receptor. Additionally, each binder is assessed to bind totumor cells, as in Example 14.

EXAMPLE 28 Effect of P28R on Mitochondrial Metabolism and Conversion ofMTS

PBMCs from eight healthy control samples and nine cancer patients withvarious diagnoses (including renal cell cancer, malignant melanoma,rectal cancer, small cell lung cancer, non-small cell lung cancer(adenocarcinoma), squamous cell carcinoma, bladder cancer, osteosarcoma,pancreatic cancer, or bronchial cancer) were cultured in a modifiedversion of the ex vivo model of Example 2 for seven days in the presenceof various quantities of P28R (SEQ ID NO: 2), and control samples wereuntreated with P28R. As shown in FIGS. 33A and 33B, the cells werecultured in either no P28R 322, 5 μg/mL 324, 10 μg/ml 326, or 20 μg/ml328 of P28R. A dose dependent stimulation of the mitochondrialmetabolism measured as conversion of MTS was observed in 5/8 (see FIG.33A) control samples and 9/9 cancer patients (see FIG. 33B). Similarresults were obtained when the PBMCs were cultured for only three days.

EXAMPLE 29 Effects of Inhibitors of Immunoregulatory Peptides onMitochondrial Metabolism and Conversion of MTS

The effect of P28R (SEQ ID NO: 2) on mitochondrial metabolism based onMTS conversion was compared to the effect of a closely related peptideP27. P27 (aka “SCF 27”) has the sequence KKLDTFFKKLSLFTER (SEQ ID NO:264), and is a variant of P28R that differs in that V8 of P28R issubstituted to K8 in P27. P28R binds to P3028 more efficiently than P27(P27 binds P3028 with a rampo score of 253, while a P28R control samplebinds P3028 with a rampo score of 308; see Example 12).

PBMCs from cancer patients with various diagnoses were cultured in amodified version of the ex vivo model of Example 2 with variousconcentrations of P28R or P27 (N=9 for P28R: N=8 for P27). Theconcentrations were either untreated control samples, 5 μg/mL(“SCF28-R5” and “SCF275”), 10 μg/ml (“SCF28-R10” and “SCF2710”), 20μg/ml (“SCF28-R20” and “SCF2720”), or 40 μg/ml (“SCF28-R40” and“SCF2740”). The results are shown in FIG. 34. While P28R stimulated thecells of cancer patients in a dose-dependent manner, P27 had no effect.

EXAMPLE 30 Effect of P28R on IL-2 Induced Proliferation (BrdUIncorporation)

The effect of P28R (SEQ ID NO: 2) on IL-2 induced proliferation wasmeasured in a BrdU incorporation assay. PBMCs from six healthy controlsamples and ten cancer patients (including renal cell cancer, malignantmelanoma, rectal cancer, small cell lung cancer, non-small cell lungcancer (adenocarcinoma), squamous cell carcinoma, bladder cancer,osteosarcoma, pancreatic cancer, or bronchial cancer) were harvested ina modified version of the ex vivo model of Example 2. One hundred pI ofculture medium (RPMI 1640 Dutch's modification (Gibco, InVitrogenAB,Stockholm, Sweden) supplemented with 200 IV/ml penicillin, 200 ul/rnlstreptomycin, 4 mM L-glutamine (all from Sigma Chemical Co. MO, US) and20% heat-inactivated human serum) were added to roundbottomed, 96-welltissue culture plates (Costar, Corning Inc. NY, US). One hundred pI ofPBMCs in RPMI/2% HAS (5×104 lymphocytes) was then added per wellfollowed by IL-2 (Proleukin, Chiron, NL) at a final concentration of 120IU/well. Control sample wells without IL-2 was set up in parallel. Cellswere cultured for 7 days in a humidified, 5% CO2-atmosphere at 37° C.Cell proliferation was assayed by incorporation of BrdU.

As shown in FIG. 35, four out of six control samples had a highproliferative response to IL-2 compared to four out of ten cancerpatients. These differences in proliferative response to IL-2 in PBMCsdemonstrated the difference existence of high and low responders toIL-2.

The response of high responders and low responders to various doses ofP28R was compared. Cells from either high responders or low responderswere cultured for 7 days with either no P28R, 5 μg/mL, 10 μg/ml, or 20μg/ml of P28R. IL-2-induced proliferation was measured as BrdUincorporation, as in the above example, and the results are shown forhigh responders in FIG. 36A, and low responders in FIG. 36B. While P28Rhad no stimulatory effect in cells from patients with a high response toIL-2 (N=4) (see FIG. 36A), P28R had a stimulatory effect on cells frompatients with a low response to IL-2 (N=6) (see FIG. 36B).

EXAMPLE 31 Effects of Inhibitors of Immunoregulatory Peptides on IL-2Induced Proliferation (BrdU Incorporation and MTS Conversion)

The effect of P27, a peptide related to P28R was compared to the effectof P28R on Il-2 induced proliferation as measured by BrdU Incorporation.P27 (aka “SCF 27”) has the sequence KKLDTFFKKLSLFTER (SEQ ID NO: 264),and is a variant of P28R that differs in that V8 of P28R is substitutedto K8 in P27. P28R binds to P3028 more efficiently than P27 (P27 bindsP3028 with a rampo score of 253, while a P28R control sample binds P3028with a rampo score of 308; see Example 12).

PBMCs from low responder cancer patients of Example 30 were cultured asin Example 30, except that some samples were cultured with variousconcentrations P28R (aka “SCF28-R”), and others were cultured withvarious concentrations of P27 (aka “SCF27”). The concentrations wereeither no peptide (“untreated cells”), 5 μg/mL, 10 μg/ml, or 20 μg/ml.BrdU incorporation was measured as in Example 30. As shown in FIG. 37,both P28R and P27 enhanced the proliferative rate of PBMC's induced byIL-2. A comparison can be drawn to the data of Example 29 and FIG. 34,in which P28R, but not P27 enhanced IL-2 stimulation of mitochondrialmetabolism, as measured by MTS conversion. P27 was observed to enhanceIL-2 stimulation of cell proliferation as measured by BrdUincorporation, but not mitochondrial metabolism as measured by MTSconversion. On the other hand, P28R was observed to enhance bothparameters. The inhibitory peptide P3028 binds to different receptors,including CD25 (see Example 8 and FIGS. 18-19) and LFA-1 (see Example 7and FIGS. 15-16), as described herein. It is contemplated that the moreefficient binder of P3028, P28R, is capable of removing P3028 from LFA-1and/or unblocking CD25. However, it is contemplated that P27 with alower/weaker binding to P3028, does not have the capacity to unblockLFA-1 but can unblock CD25. Thus, it is contemplated that differentpopulations of patients may be affected in different ways byimmunoregulatory peptides such as P3028. Moreover, it is contemplatedthat different inhibitors of immunoregulatory peptides can modulate theactivity of different receptors, and/or different signal transductionpathways.

EXAMPLE 32 Comparison of MTS and BrdU Assays

The two cell proliferation assays in this study are both widely used inorder to measure cell proliferation. Peptide P28R had a stimulatoryactivity of MTS conversion in seven day cultures of PBMCs in 9/9patients and in 5/8 healthy control samples. In contrast, P28Rstimulated incorporation of BrdU in seven day cultures of PBMCs fromonly 1/6 and 2/10 patients.

IL-2 induced proliferation, measured as incorporation of BrdU, wasstimulated by P28R in PBMC cultures from cancer patients with a lowproliferative response to IL-2 (experimental conditions were asdescribed in Example 30). PBMCs from 2/3 healthy control samples and 2/4cancer patients were not stimulated by IL-2 when the effect was measuredas MTS conversion (experimental conditions were as described in Example28). However, PBMCs from all these persons (“non-responders”) who didnot respond when measured with MTS were significantly stimulated by IL-2when the effect was measured as incorporation of BrdU.

The above results are illustrated in FIG. 38. PBMC cultures from twodifferent patients (A, B) and (C, D), with IL-2 382 (bars on left) orwithout IL-2 384 (bars on right). The effect of IL-2 and the peptidesP28R (aka “SCR28R”) and P27 (aka “SCF27”) were measured atconcentrations of either no peptide (“untreated cells”), 5 μg/mL, 10μg/ml, or 20 μg/ml of peptide.

In two patients, the response to IL-2, measured as BrdU incorporation,was enhanced by P28R (see FIGS. 38A and 38C), but this effect of P28Rwas only observed in one of these patients when MTS conversion was used(see FIG. 38B). Thus, while in one patient (see FIGS. 38A and 38B) thestimulatory activity of IL-2 was registered using both BrdU and MTS, inthe other patient, the stimulatory activity of IL-2 was registered usingBrdU only (see FIG. 38C). Based on these observations, it is concludedthat effects on the metabolic activity measured as MTS conversion doesnot always correlate with DNA synthesis measured as incorporation ofBrdU.

Additionally, P28R enhanced the effect of IL-2 measured both with BrdUand MTS, but the stimulatory effect of SCF27 was observed only when BrdUincorporation is measured. In the patient shown in C the results arevery similar to those shown in A, but in D no stimulatory effect is seenwhen the effect is determined using MTS conversion.

These results indicate that albumin-derived immunomodulatory structuressuch as P3028 appear to modulate signal transduction through differentmechanisms. Thus, different patient populations can respond differentlyto inhibitors of immunomodulatory peptides. It is contemplated that invitro diagnostic assays can be helpful in identifying which patientshave albumin-derived immunomodulatory structures, and can be furtherhelpful in identifying which patients will respond to certain inhibitors(or combinations of inhibitors) of immunomodulatory structures.

EXAMPLE 33 Effects of Binders of Immunoregulatory Peptides on LymphocyteActivation

Binders of immunoregulatory peptides, for example the peptides of Tables5.1, 6.1, 6.2, or 12 (SEQ ID NOs: 1-32, 265-393), or SEQ ID NOs: 34,46-53, 64-66, 68, 76, 94-96, 98, or 264, are assayed for effects onlymphocyte activation, as in Example 13. Analyses of these peptides areperformed in human ex vivo models. The stimulatory activity on PBMCs,measured using the MTS or CFSE techniques, are studied in 7 healthycontrol samples and 7 cancer patients of various diagnoses. The peptidesare assayed for stimulatory activity even in the absence of other typesof stimulation, and are compared to untreated control samples.

Stimulatory activity of the peptides of Tables 5.1, 6.1, 6.2, or 12 (SEQID NOs: 1-32, 265-393), or SEQ ID NOs: 34, 46-53, 64-66, 68, 76, 94-96,98, or 264 on a proliferative response to IL-2 suppressed by a P3028sequence or structure. PBMCs are cultured for 7 days with IL-2 and theproliferative rate is determined as incorporation of BrdU. Each set ofconditions is assayed in triplicate. Initial proliferation of PBMCs iscompared to proliferation of PBMCs from the same donor after treatmentwith each peptide.

EXAMPLE 34 Binding of Inhibitors of Immunoregulatory Peptides to TumorCells

A biotinylated version of each of the P28R peptides of Tables 5.1, 6.1,6.2, or 12 (SEQ ID NOs: 1-32, 265-393), or SEQ ID NOs: 34, 46-53, 64-66,68, 76, 94-96, 98, or 264, each of which has been shown to bind toP3028, is used to assay binding of the peptide to tumor cells. Fivebreast cancers, two renal cell carcinomas and four malignant melanomasare analyzed, as in Example 14.

EXAMPLE 35 Unblocking the LFA-1 Receptor by Inhibitors ofImmunoregulatory Peptides

As described herein, β2-integrins play a role in the normal function ofthe immune system. Also described herein are immunosuppressor mechanismsbased on the binding of an endogenous inhibitor, P3028, to theβ2-integrin LFA-1. As described in Example 7, the membrane staining ofPBMCs from cancer patients is markedly decreased compared to normalcontrol samples. The exposure of LFA-1 could, however, be enhanced byincubating PBMCs from cancer patients with an antibody directed againstthe inhibitor P3028 (see Example 7 and FIG. 16).

Staining for LFA-1 is performed with the anti-LFA-1 antibody of Example7 and a secondary antibody (Ultravision) followed by development withFast Red. Fresh frozen tumor sections without any fixation are incubatedfor 4-20 hours with each of the P28R peptides of Tables 5.1, 6.1, 6.2,or 12 (SEQ ID NOs: 1-32, 265-393), or SEQ ID NOs: 34, 46-53, 64-66, 68,76, 94-96, 98, or 264, each of which has been shown to bind to P3028,before staining for LFA-1. For comparison, control sample tumor sectionswere incubated with phosphate buffered saline only. The amount ofanti-LFA-1 antibody staining is observed, and used to determine theamount of blocking, if any, of the LFA-1 receptor. Migration andcytotoxic activity of treated cells is also ongoing.

EXAMPLE 36 Positional Scans of Amino Acid Residues in SEQ ID NO: 2

Positional scan data was used to study the influence of substitution ofdifferent types of amino acids in each position of P28R (SEQ ID NO: 2)on the binding of P3028 (SEQ ID NO: 185). Each amino acid in the peptidesequence of P28R (SEQ ID NO: 2) was exchanged with all of the naturallyoccurring amino acids, and immobilized on a solid phase chip. Thebinding of P3028 to these “mutated” P28 R peptides synthesized on a chipwas determined using the ELISA technique. The results are summarized inTable 13. In view of the results, Table 13 includes a column identifyingoptional substitutions at each position that can maintain binding toP3028.

TABLE 13 Analysis of P3028 Binding to Solid Phase P28R Variants OptionalSubstitutions Substitution that maintain Position Category ELISA signalAvg 3028 binding K1 RHK 523 428 366 439 any type of amino DE 373 396 385acid possible AVIL (SEQ 466 442 483 449 460 ID NO: 813) M 457 457 FYW332 315 284 310 STNQ (SEQ 344 493 445 455 434 ID NO: 814) K2 RHK 417 394445 419 positively charged DE 335 349 342 amino acids AVIL (SEQ 309 317331 343 325 preferable, F and ID NO: 813) N possible* M 400 400 FYW 390301 304 332 STNQ (SEQ 281 331 432 350 349 ID NO: 814) L3 RHK 370 477 386411 any type of amino DE 492 528 510 acid possible AVIL (SEQ 427 377 454375 408 ID NO: 813) M 460 460 FYW 393 344 341 359 STNQ (SEQ 393 451 374473 423 ID NO: 814) D4 RHK 317 317 274 303 any type of amino DE 414 417416 acid possible AVIL (SEQ 494 424 430 303 413 ID NO: 813) M 384 384FYW 380 422 443 415 STNQ (SEQ 344 405 296 345 348 ID NO: 814) T5 RHK 430391 237 353 polar uncharged DE 295 341 318 amino acids AVIL (SEQ 346 374293 311 331 preferable, R, Y ID NO: 813) and W are M 475 475 possible*FYW 290 425 418 378 STNQ (SEQ 458 424 436 535 463 ID NO: 814) F6 RHK 309332 309 317 hydrophobic and DE 193 229 211 uncharged polar AVIL (SEQ 575547 466 408 499 amino acids are ID NO: 813) preferable; avoid M 467 467positively and FYW 437 364 348 383 negatively STNQ (SEQ 432 481 446 410442 charged ID NO: 814) F7 RHK 369 364 232 322 hydrophobic and DE 301381 341 uncharged polar AVIL (SEQ 426 527 446 517 479 amino acids areID NO: 813) preferable; avoid M 712 712 positively and FYW 460 334 380391 negatively STNQ (SEQ 700 517 348 511 519 charged ID NO: 814) V8 RHK365 213 253 277 hydrophobic non- DE 122 139 131 aromatic carbonAVIL (SEQ 299 308 401 411 355 chain amino acids ID NO: 813)are preferable, M 221 221 F possible, avoid FYW 358 211 228 266negatively STNQ (SEQ 216 298 203 271 247 charged ID NO: 814) K9 RHK 374306 377 352 positively charged DE 149 240 195 amino acids AVIL (SEQ 191248 190 166 199 preferable, polar ID NO: 813) uncharged M 283 283T and Q possible FYW 174 198 245 206 STNQ (SEQ 274 347 256 330 302ID NO: 814) L10 RHK 439 293 285 339 any type of amino DE 102 81 92acid except AVIL (SEQ 426 658 415 348 462 negatively ID NO: 813)charged are M 460 460 possible FYW 403 382 316 367 STNQ (SEQ 351 399 365470 396 ID NO: 814) S11 RHK 333 535 323 397 polar uncharged DE 322 234278 amino acids are AVIL (SEQ 318 392 289 213 303 preferable, H isID NO: 813) possible* M 744 744 FYW 250 402 324 325 STNQ (SEQ 442 520451 768 545 ID NO: 814) L12 RHK 483 460 355 433 any type of amino DE 8982 86 acid except AVIL (SEQ 462 545 456 428 473 negatively ID NO: 813)charged M 499 499 FYW 389 320 409 373 STNQ (SEQ 478 437 462 651 507ID NO: 814) F13 RHK 502 1046 220 589 any type of amino DE 112 98 105acid except AVIL (SEQ 525 446 468 448 472 negatively ID NO: 813)charged* M 1190 1190 FYW 402 291 430 374 STNQ (SEQ 635 494 862 1144 784ID NO: 814) T14 RHK 264 463 259 329 any type of amino DE 159 110 135acid except AVIL (SEQ 305 380 375 360 355 negatively ID NO: 813) chargedM 501 501 FYW 348 270 374 331 STNQ (SEQ 369 319 599 301 397 ID NO: 814)E15 RHK 237 318 324 293 negatively DE 404 371 388 charged aminoAVIL (SEQ 174 163 163 246 187 acids preferable, ID NO: 813)possibly Y or Q M 247 247 FYW 137 340 226 234 STNQ (SEQ 165 152 161 344206 ID NO: 814) R16 RHK 260 239 291 263 any type of amino DE 133 107 120acid except AVIL (SEQ 226 254 176 217 218 negatively ID NO: 813) chargedM 238 238 FYW 297 311 202 270 STNQ (SEQ 184 292 311 133 230 ID NO: 814)*It is noted that M has a sulfur atom in the side chain, and withoutbeing limited by any theory, it is contemplated that substitution of Monly at positions 8, 9, and/or 15 can result in reduced binding of theinhibitor peptide to P3028.

It was noted that the following categories of amino acid residues at thefollowing positions are likely to be involved in binding of P3028 toP28R (some additional “possible” substitutions are noted in Table 13):

K2 positive charged amino acids

T5 polar uncharged amino acids

F6 hydrophobic and uncharged polar

F7 hydrophobic and uncharged polar

V8 hydrophobic, non-aromatic carbon chain amino acids

K9 positively charged amino acids

S11 polar uncharged amino acids

E15 negatively charged amino acids

Thus, in some embodiments, a central core, T5-S11, and two additionalamino acids, K2 and E15, are identified to be involved in the binding ofthe peptide P3028.

From the positional scan data it is also noted that a “core peptide” canbe identified, FFVKLS (SEQ ID NO: 62) (also referred to herein as “P28core”), bind the 3028 peptide as efficiently as the full length peptideP28R. However, the P28 core peptide does not stimulate PBMC activation(CD69 and CD71) in short term cultures of this model, while the P28Rpeptide does stimulate PBMC activation in short term cultures of thismodel.

However, in cultures with human and dog cancer sera, P28 core has astimulatory activity. As such, without being limited by any theory, itis contemplated that P28 core can be useful in de-blocking inhibitoryeffects of P3028 (e.g. displacing bound 3028 structures from thecellular receptors). For example, in some embodiments, P28 core can beuseful in de-blocking P3028-mediated inhibition of the LFA-1 receptor.

Based on the positional scan data, it is contemplated that substitutionsof SEQ ID NO: 2 could be useful in binding P3028, de-blocking the LFA-1receptor from P3028-mediated inhibition, and/or stimulating immunecells.

EXAMPLE 37 Effect of Modified Peptides on PBMC Activation

The activity of peptide P28R (SEQ ID NO: 2) and modifications of P28Rwas studied in a human ex vivo model using PBMCs in short term cultures,24 or 48 hours. Effects of P28R and modifications of P28R on PBMC's froma healthy control person were studied. Activation was measured aspercentage of cells with enhanced marker CD69 using flow cytometry.PBMCs were incubated with the peptides (40 μg/mL) for 24 hours in RPMIplus 10% human AB serum.

The influence of various amino acid substitutions on the stimulatoryeffect (measured as expression of CD69) in this ex vivo model wasstudied. Stimulatory effects of P28R and amino acid substitutions thatexhibit a good binding capacity according to the positional scan wereassessed. P28R (KKLDTFFVKLSLFTER) (SEQ ID NO: 2), peptide 30677(KKLDTFFVKLSLMTER) (SEQ ID NO: 583), peptide 30678 (KKLDTFFVKLQLFTER)(SEQ ID NO: 584), and peptide 30680 (KKLDTVMVKLQLMTER) (SEQ ID NO: 585)were examined (see FIG. 41A). FIG. 41A illustrates the results of twoexperiments (410 and 412) for each peptide. All four peptides inducedactivation of PBMCs from the healthy control person.

P28R (SEQ ID NO: 2), peptide 30864 (KSLDTFFVKLSLFTER, SEQ ID NO: 586);peptide 30685 (KKLDTFFVKLSLFTFR, SEQ ID NO: 587); peptide 31135(KKLDTFFVYLSLFTER) (SEQ ID NO: 588); peptide 31136 (KKLDTFFVNLSLFTER)(SEQ ID NO: 589), and peptide 31138 (KKLDTFFVDLSLFTER) (SEQ ID NO: 591)were examined (see FIG. 41B). FIG. 41B shows two experiments (414 and416) for each peptide. Peptide 31135 also stimulated immune cells.Accordingly, in addition to the analysis of Table 13, tyrosine may alsobe substituted in position 9 of SEQ ID NO: 2 in accordance with someembodiments herein.

These results show general agreement with the data from the analysisbased on the positional scan in Table 13 (see Example 36). Without beinglimited by any theory, some differences between the position scan dataand immune cell stimulation data are not inconsistent with thedisclosure herein. It is noted that Table 13 relates to ability to bindto P3028 in an ELISA assay, while FIGS. 41A-B relates to an assay forPBMC activation. In some embodiments, a peptide comprising, consistingessentially of, or consisting of SEQ ID NO 2 or 583-585 stimulateshealthy immune cells, for example PBMC's.

EXAMPLE 38 Effect of P28 Core Peptide on PBMC Activation

As observed in Example 37, P28R (SEQ ID NO: 2) can stimulate PBMC's fromhealthy controls in short term cultures when RPMI plus 10% normal humanAB serum is used as culture medium. Truncations of P28R were alsoassessed for their ability to activate PBMC's. PBMCs were incubated withthe peptides (40 μg/mL) for 24 hours in RPMI plus 10% human AB serum.PBMC activation was measured as percent cells with enhanced expressionof either CD69 (FIG. 42A) or CD71 (FIG. 42B) using flow cytometry. Twoexperiments were performed for each peptide.

As shown in FIGS. 42A and 42B, peptide P28R (SEQ ID NO: 2) effectivelyactivated healthy PBMC's in this model, but peptide 32251 (SEQ ID NO:592) and peptide 32230 (“P28 core”) (FFVKLS) (SEQ ID NO: 62) did notactivate healthy PBMC's in this model.

However, in PBMC cultures where normal human AB-serum in the culturemedium was substituted for by sera from dogs with cancer or humanpatients with cancer, P28R (SEQ ID NO: 2) and P28 core (peptide32230(FFVKLS) (SEQ ID NO: 62) each activated PBMCs, measured as enhancedexpression of CD69 (see FIG. 43). FIG. 43 shows a comparison between thefull length peptide P28R (SEQ ID NO: 2) and the 6 amino acid P28 coresequence (peptide 32230) (FFVKLS) (SEQ ID NO: 62) in culture mediumcontaining sera from two different cancer patients (human ca serum 1 430and human ca serum 2 432). Both P28R (SEQ ID NO: 2) and P28 core (SEQ IDNO: 62) activated PBMCs in the presence of cancer serum.

In addition, biotinylated P28R has been shown to bind directly to PBMCsas demonstrated by immunocytochemistry or rosetting of P28R coated beads(binding of beads to the cells).

Taken together, these results show that P28R (SEQ ID NO: 2) can bind toP3028 and de-block cellular receptors and can also have a directstimulatory activity on immune cells. Additionally, P28 core (SEQ ID NO:62) can bind to P3028 and de-block Cellular Receptors.

EXAMPLE 39 Cytotoxic Activity of P28R

The effect of P28R (SEQ ID NO:2) was further studied in in vivo modelsin nude and immunocompetent mice. Injection of P28R intra-tumorally intohuman pancreas cancer in a xenograft model in nude mice demonstrated acapacity to induce tumor cell apoptosis after one day. FIGS. 44A and 44Bshows immunohistochemical staining for Caspase 3 (440), indicating anongoing apoptosis) with a significantly enhanced activation of thisenzyme in P28R treated tumors (FIG. 44A) compared to tumors which weretreated with the drug solvent only (FIG. 44B). An absence of staining isalso indicated 442. It is noted that the results shown were obtainedonly one day after administration of P28R in animals with no capacity toform an immune reactivity to the tumor.

As such, intra-tumoral administration of P28R a can have a cytotoxicaction on tumor cells in accordance with some embodiments herein. Insome embodiments, P28R has a direct cytotoxic action on tumor cells.

EXAMPLE 40 Therapeutic Activity of P28R

The capacity of P28R (SEQ ID NO: 2) to activate the immune system andthereby induce tumor cell-lysis was studied in immunocompetent mice,C57B1, with inoculated B16 melanoma. P28R, 40 microgram in 100microliter, was injected intra-tumorally and the tumors were taken outafter 3 days. As shown in FIG. 45, the dominating cells in the tumorsafter this treatment are inflammatory cells, which were identified byimmunohistochemical staining 450 using a polyclonal rabbit anti-CD45antibody (FIG. 45A). For comparison a control tumor section wasincubated with rabbit IgG at the same concentration (FIG. 45B). Anabsence of staining is also indicated 452.

Accordingly, it was demonstrated that P28R can induce infiltration of aB16 melanoma tumor by inflammatory cells. In accordance with someembodiments herein, P28R can induce infiltration of tumors, for examplemelanomas, by immune cells.

EXAMPLE 41 Effects of Modified Peptides on Immune Cell Stimulation

The influence of various amino acid substitutions and additions on theimmunostimulatory effect was studied. Effects of modified peptides onactivation of PBMCs from healthy control person were assessed.Activation was determined as percentage of cells with enhanced markerCD69 or CD71 using flow cytometry. PBMCs were incubated with thepeptides (40 μg/mL) for 48 hours in RPMI plus 10% human AB serum. Twoexperiments (460 and 462 in FIG. 46A; 464 and 466 in FIG. 46B,respectively) were performed for each peptide. Peptides P28R (SEQ ID NO:2), P28 core (peptide 32230) (SEQ ID NO: 62), 32251 (KKLDTFFPKLSLFTER)(SEQ ID NO: 592), 32814 (RKLDTFFVKLSLFTERRR) (SEQ ID NO: 586), 32815(KKLDQFFVKLSQHNER) (SEQ ID NO: 595), 32665 (SEQ ID NO: 593), and 32819(SEQ ID NO: 594) were tested.

As shown in FIG. 46, peptide 32814 (SEQ ID NO: 586), had a stimulatoryeffect in short term cultures similar to that of P28R (SEQ ID NO: 2)(batch CS8040). Accordingly, peptide 32814 (SEQ ID NO: 591) activatedhealthy PBMCs as indicated by enhanced CD69 (FIG. 46A) and also byenhanced CD71 (FIG. 46B).

EXAMPLE 42 Diagnostic Uses

In addition to therapeutic applications, diagnostic applications of P28Rand truncations and modifications thereof were also contemplated. Forexample, information about patients systemic and local (intra-tumoural)immune status can be obtained using reagents comprising P28R, or atruncation or modification thereof.

It is contemplated that the occurrence of immunoinhibitory3028-structures in tumors can be identified by immunohistochemicalstaining using either an antibody directed against P3028 or usinglabeled P28R (SEQ ID NO: 2) or P28 core (SEQ ID NO: 62), for examplebiotinylated P28R or P28 core. FIG. 47 shows two areas of a human breastcancer stained using biotinylated P28R. Staining 470 is observed in FIG.47B. Staining is not observed in FIG. 47A. An absence of staining isindicated 472.

As such, areas of tumors comprising P3028 structures (as well as areasnot comprising these structures) can be identified using labeledpeptides in accordance with embodiments herein.

EXAMPLE 43 Treatment of a Tumor Using a P28 Peptide Inhibitor

A patient having a melanoma is identified. A pharmaceutical compositioncomprising 40 μg/100 ml of a peptide consisting of the amino acidsequence SEQ ID NO: 2 and a PBS buffer formulated as a gel-likesubstance is injected peri-tumorally in the patient once a week forthree weeks. Tumor cytotoxicity is observed. Immune cell invasion of thetumor is observed.

EXAMPLE 44 Treatment of a Tumor Using a P28 Core Peptide Inhibitor

A patient having breast cancer is identified. A pharmaceuticalcomposition comprising a 80 μg/100 ml of a peptide consisting the aminoacid sequence SEQ ID NO: 62 and a tris buffer formulated as a gel-likesubstance is injected peri-tumorally in the patient. Immune cellinvasion of the tumor is observed.

EXAMPLE 45 Treatment of a Tumor Using a P28R-Modification PeptideInhibitor

A patient having prostate cancer is identified. A pharmaceuticalcomposition comprising 1 mg/kg of a peptide consisting of the amino acidsequence SEQ ID NO: 586 dissolved in an aqueous buffer is administeredsystemically to the patient once every two days for five totaladministrations. Tumor cytotoxicity is observed. Immune cell invasion ofthe tumor is observed.

What is claimed is:
 1. A method of inhibiting cancer in an individual,comprising administering to an individual in need thereof a compositioncomprising an isolated peptide comprising the amino acid sequence FFVKLS(SEQ ID NO: 62), wherein the cancer is selected from the groupconsisting of colorectal cancer, renal cancer, breast cancer, prostatecancer, pancreatic cancer, melanoma, small cell lung cancer, non-smalllung cancer, squamous cell carcinoma, bladder cancer, osteosarcoma,bronchial cancer, and ovarian cancer.
 2. The method of claim 1, furthercomprising diagnosing the individual as having the cancer.
 3. The methodof claim 1, wherein the isolated peptide is no more than 30 amino acidresidues in length.
 4. The method of claim 1, wherein the isolatedpeptide is no more than 20 amino acid residues in length.
 5. The methodof claim 1, wherein the isolated peptide comprises the amino acidsequence KKLDTFFVKLSLFTER (SEQ ID NO: 2).
 6. The method of claim 1,wherein the isolated peptide consists of the amino acid sequenceKKLDTFFVKLSLFTER (SEQ ID NO: 2).
 7. The method of claim 1, wherein theisolated peptide comprises the amino acid sequence RKLDTFFVKLSLFTERRR(SEQ ID NO: 586).
 8. The method of claim 1, wherein the isolated peptideconsists of the amino acid sequence RKLDTFFVKLSLFTERRR (SEQ ID NO: 586).9. The method of claim 1, wherein the isolated peptide consists of theamino acid sequence FFVKLS (SEQ ID NO: 62).
 10. The method of claim 1,the method further comprising administering a second therapeutic agentto the individual.
 11. The method of claim 1, wherein the cancer issquamous cell carcinoma.
 12. The method of claim 1, wherein the serum,plasma, or tumor of the individual comprises a damaged albumin, anaggregate of albumins, an albumin fragment, or a second peptide; andwherein the albumin fragment or second peptide comprises at least one ofSEQ ID NOs: 183-246.
 13. The method of claim 1, wherein the isolatedpeptide induces at least one of the following in said individual: (a)activation of an immune cell; (b) inhibition of binding of a damagedalbumin, an aggregate of albumins, an albumin fragment, or a secondpeptide to a lymphocyte function-associated antigen 1(LFA-1) receptor oran interleukin 2 (IL-2) receptor, wherein the second peptide or albuminfragment, if present, comprises at least one of SEQ ID NOs: 183-246; or(c) cytotoxicity to a cancer cell.
 14. The method of claim 13, whereinactivation of the immune cell comprises immune cell proliferation,activating or enhancing expression of cluster of differentiation 69(CD69) and/or cluster of differentiation 71 (CD71), induction ofsecretion of interferon gamma (IFNγ) or interleukin 12 (IL-12),induction of secretion of perforin or granzyme B, enhanced cytotoxicity,cytokine production, cell migration, cell proliferation, recruitment ofimmune effector cells to a tumor, or combination thereof.
 15. The methodof claim 1, wherein inhibiting the cancer comprises inhibitingimmunosuppression in the individual.
 16. The method of claim 1, whereinthe individual comprises a damaged albumin, an aggregate of albumins, analbumin fragment, or a second peptide bound to an immune cell of theindividual, wherein the albumin fragment or second peptide comprises atleast one of SEQ ID NOs: 183-246.